how to clear com port assignments in windows 10

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How to Free (Reset) COM Port in Use in Windows

When you connect a new COM, USB, or Bluetooth device to your computer, Windows assigns the first available free COM port number from 1 to 256 to the device (COM1, COM2, COM3, etc). Even after the device is disconnected, the assigned COM port number is not released and remains reserved for the device (Windows shows it as “in use”). Some legacy apps can only use low COM port numbers from 1 to 9. In order for such an application and device to work properly, you should change the assigned COM port number or completely release the reserved COM ports used by other app.

Note . Virtual COM ports are still widely used in Windows, although modern computers almost never have physical serial COM ports on the motherboard. For example, virtual COM ports are currently used by USB (USB-to-UART, USB-to-COM, USB modem, card/RFID reader) and Bluetooth adapters.

How to Change the COM Port Number in Windows

The administrator can manually change the assigned COM port number for the device using the Device Manager.

• Open the Device Manager (press Win + R and run devmgmt.msc )
• Expand Ports (COM & LPT) ;

These steps won’t help if Windows says you that the COM port you need is already in use. In this case, try to manually reset the used COM port and then reassign it to a new device.

Reset COM Port in Use on Windows

If the device is not currently connected to the computer, you can reset its assigned COM port number.

• Expand the Ports (COM & LPT) section. Disconnected devices have the reserved COM port number in their names and greyed out icons;

• DO NOT check the option “Delete the driver software for this device”;
• Repeat these steps until all grayed-out COM ports are removed;
• Now you can assign a free COM port number to the device you want as described above.

How to Find Which Process is Using the Serial (COM) Port

COM ports are used by devices in Windows in exclusive mode. A COM port cannot be released or deleted if it is being used by another running process. In this case, use the Process Explorer to find out which Windows app is using the COM port.

• Go to the Device Manager , expand Ports (COM & LPT) , right-click on the COM port you want to check, and select Properties ;
• Go to the Details tab, select Service from the Property dropdown list ;

• Download the Process Explorer utility from Microsoft;

• Paste the COM port handle you copied from Device Manager into the Handle or DLL substring search box ( serial in this case) and click Search;

• Then you can reassign the COM port number to another device.

Clear COM Ports Using the COM Name Arbiter

The free third-party tool COM Name Arbiter can be used to release unused COM ports and change assigned port numbers. Download the COM Name Arbiter Tool from the official website and run as an Administrator.

The tool shows list of COM ports with checkmark next to the currently busy ports of connected devices. Press the Remove non-present devices to clear all assigned COM port number reservations.

You can also clear the COM port manually, by unchecking a specific device from the list.

Another handy tool for viewing COM port configuration is COM Port Info . This tool allows you:

• View assigned COM port numbers;
• Safely remove hardware;
• Change and swap COM port numbers;
• Reset USB Ports.

Removing Unused COM Ports via CMD

The built-in PnPUtil tools can be used to list and remove assigned COM port numbers from the command prompt.

List COM port devices:

In this example, the COM3 port is assigned to a MediaTek USB Port device. This device is currently Disconnected .

Copy and paste the Instance ID into the following command to remove this COM device reservation:

Reset COM Ports Reservation via the Registry Editor

The following low-level method of removing all COM port reservations in Windows requires direct modification of the system registry. Windows stores COM port assignments in the registry value of the ComDB parameter under the reg key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter . You can make direct changes to the registry to reset COM port reservations.

Caution . Create a system restore point before making these registry changes.

• Disconnect any peripheral devices from the computer;
• Open the Registry Editor (regedit.exe);
• Go to the reg key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter ;

• Restart your computer. When it boots back, connect all the COM devices in the proper order.

Now you know how to delete COM ports and reassign them to a different device.

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  Windows OS Hub / Windows 10 / How to Clean Up or Reset COM Port Numbers in Windows

How to Clean Up or Reset COM Port Numbers in Windows

When you connect a new COM device or a USB device to your computer (USB modem, mobile phone, Bluetooth adapter, serial to USB converters, etc.), Windows detects it using Plug-n-Play and assigns it a COM port number in the range of 1 to 255 (COM1, COM2, COM3, etc.). If this device is connected again, the reserved COM ( Communication , or Serial ) port number is assigned to it. A new device gets the first free COM port number. It often happens that when connected, external devices create several COM ports at once. In my case after connecting a Bluetooth adapter 10!!! new COM ports have appeared in the system.

A number of legacy applications are able to address only two-digit COM port numbers, and won’t work with COM100 and higher. In the worst cases, these programs work only with COM1-COM9 ports. What if a device has got a higher COM port number?  Is it possible to reset the numbering for reserved COM ports and delete assigned ports?

How to Change a COM Port Number for a Device in Windows?

Find out which process is using a serial com port in windows, resetting com port numbers in windows registry.

In Windows, you can manually change the COM port number assigned to a device. Suppose the necessary COM port is already busy, and you want to try to free it.

• Open the Device Manager by running the devmgmt.msc command;

• Then expand Ports (COM & LPT) and find your device in the list;
• Go to the Port Settings tab and click the Advanced button;
• The current COM port number assigned to the device can be found in the COM Port Number field;

But more often you cannot change the assigned COM port number to another one in the hardware properties, since all the “lower” COM ports are already in use.In this case, you need to try to remove the COM port reservation

• Expand the Ports (COM & LPT) branch, find which COM port number you need is assigned to (a pale icon means that this COM port is assigned, but this device is not currently connected);

However, this method does not allow you to free the busy COM port in all cases.

Get-WMIObject Win32_SerialPort | Select-Object Name,DeviceID,Description You can get the COM port number for a specific device by its name, for example:

Get-WMIObject Win32_SerialPort | Where-Object { $_.Name -like "*Arduino*"}|select name, deviceid or Get-WMIObject Win32_SerialPort | Where-Object { $_.Name -like "*GPS*"}|select name, deviceid

You won’t be able to release the COM port of a device that is used by Windows or a running program (process). First, you need to stop the process that is currently using the COM port. You can use the Process Explorer tool (by Sysinternals) to find out the name of the process using a particular COM port number ( https://docs.microsoft.com/en-gb/sysinternals/downloads/process-explorer ).

First, you need to display the name of the service that uses the COM port. Run the PowerShell command:

get-pnpdevice -class Ports -ea 0| Select Name, PNPDeviceID, Status, Service

The service name of the specific COM port is shown in the Service column. For example, for COM2 it is Serial . Now you need to run Process Explorer as an administrator and select Find -> Find Handle or DLL from the menu. In the Handle or DLL substring line, enter the Service value obtained earlier. In our example, this is Serial .

Process Explorer should show the process name that is currently using your COM port. To release the COM port, kill the process or program.

Information about the COM ports in use is stored in CommDB registry parameter under the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter reg key.

• Unplug all external devices and restart your computer;
• After the reboot, connect the devices in the necessary order, reinstall USB-to-serial converters, etc. All detected COM port devices will be automatically detected by the system and assigned sequential COM port numbers.

You can also use the following free tools to clean up reserved COM ports:

• Device Cleanup Tool – the utility is used to search the registry for previously connected devices (under the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum ), remove unused devices, and clear COM port reservations.

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Hi dear When I open Device Manager there is no branch of (COM & LPT) to expand. How can I Add or Find it?

thank you so much

thanks you so much , life saving post 🙂 , i mostly work with iot devices and sometime com ports get busy and am getting com port busy returns in code so this saved my life in flushing com port

Thank you for the post, very helpful

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Windows Tip- How to Clear, Reset, & Disable New Com Port Numbers

Windows Tip- How to Clear, Reset, how to disable new com port numbers

Note: Removing all this stuff still doesnt remove the device… when you plug it back in again all the same stuff comes back so on windows 10 go to Start-> Settings->Devices->

Try removing from this location… you have to connect to remove

Hi there, Just to put a bow on this topic, there are some other recognizes methods as well. Whenever this has cropped up, I choose this way to handle it and I always reboot when making changes at a system or OS level.

To remove unused COM ports from Windows 10, you can:

• Right-click on the COM port
• Select Uninstall
• Do not check the box that says “delete the driver software for this device”

You can also remove COM ports by:

• Clicking Start
• Selecting Run
• Typing regedit and clicking OK
• Navigating to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter
• Selecting all in the Data section
• Selecting Reset to zero (0)
• Closing the registry editor
• Restarting your computer

You can also use the Command Prompt to check the COM port:

• Type devmgmt.msc to open the Device Manager
• Select View > Show hidden devices
• Open the Ports (COM & LPT) section

You can also use COM Name Arbiter to remove most of the risk associated with modifying the Registry.

I use this method myself, "Device Manager window open. Click “View” in the menu and select “Show hidden devices”. Expand “Ports” to list all COM ports used. Right click on one of the greyed out ports and select “Uninstall” . thats it. Reboot.

also if you use device manager to remove com port make sure to select → View → Show Hidden Devices

speed reader over there,LOL

sometimes the reply is not necessarily for you… but for the others…lol … i still thought you were talking about in regedit…

“We do it nice, cause we do it TWICE…”

The way you can tell it has been removed completely is if you plug it in usb the message pops up installing JTAG or whatever… if that doesent come up you know that the device is cashed SOMEWHERE on the system… deleteing all that stuff still didnt COMPLETELY remove the device because when you reconnect it doesnt show that message and goes right back to its previous COM port number… the Start-> Settings->Devices-> was the only way i could get to the complete removal

COM port in Windows 10 & 11: fix any COM port-related issues in 2 easy ways

In this article, we are going to discuss two ways to resolve the problem of the lack of COM ports on computers running the Windows 10 and/or 11 operating system . Windows 10 and/or 11 COM port issues plague many users whose computers have been designed without the inclusion of any serial interfaces. The absence of physical COM ports can hinder a user’s ability to make use of computing peripherals that transmit their data serially.

The way to resolve this issue is through the use of Windows virtual serial ports. It can be very frustrating to query your Device Manager with the expectation of finding COM ports only to find that they are not present. We are going to show you two different methods you can use to add COM ports to Windows 10 and Windows 11 . One is a procedure that employs the native functionality built into the operating system and the other uses third-party software.

The Problem: Windows 10 COM ports not showing in device manager

Finding virtual COM port in Windows 10 causes issues for some users. Individuals navigate to their Device Manager, anticipating that they’ll find virtual COM port drivers previously loaded on their machine.

However, when they open their Device Manager, they’re perplexed and frustrated once they realize these COM ports aren’t listed.

The reason being, said serial port option may not be available because of the Windows 10 update installation.

The update could impact virtual serial port drivers ability to load specific devices by default. This creates a major problem for those using such (seemingly) incompatible devices.

There are several solutions. One option is to find com port Windows 10 by following the steps below:

Step 1: Open the Device Manager.

Step 2: From the menu bar, click View.

Step 3: Choose “Show hidden devices”.

Step 4: From the list of hidden devices, find the Ports (COM & LPT).

Step 5: Expand the same menu (“+”) to check for the missing COM ports.

If you can't find com ports this way, the next step is investigating how it can be done with Electronic Team’s Virtual Serial Port Driver for Windows 10 virtual serial ports.

To ensure the easiest solution possible, see our step-by-step procedure below. A process that can help users eliminate problems with their COM ports on Windows 10 in as few as three clicks.

Keep reading to learn how easy and convenient it is to use this Windows 10 virtual COM port driver.

Add COM port Windows 10 with Virtual COM Port Driver

When the COM and LPT ports do not appear in your Windows 10 Device Manager your ability to perform your work is negatively impacted. There is a way to resolve this annoying problem in a manner that will prevent it from recurring. The solution is to install the aforementioned Virtual COM Port Driver from Electronic Team . This application allows the creation of an unlimited number of virtual serial port pairs. The virtual COM port pairs employ a virtual null-modem connection to enable communication with each other.

• Virtual COM Port Driver

Virtual Serial Port Driver

Users engaged in the practice of developing and testing serial applications and hardware will benefit from the configuration options that are possible through the use of Virtual Serial Port Driver. One example is the ability to allow two applications to share data via virtual serial ports. Connecting the apps with a pair of virtual COM ports lets the data written by one program be immediately made available to the other program. This can save significant time and effort when debugging and testing serial apps and devices.

Step-by-step guide to add virtual COM port Windows 10:

Create virtual COM ports in Windows 10 with USB Serial Converters

Most often, virtual COM ports in Windows 10 install automatically when a user connects a converter to a computer with internet access. Unfortunately, there are Serial Converter device drivers that won’t automatically install on certain operating systems.

This is not a major issue, as users can simply install the drivers utilizing the disk that comes with their specific Serial Converter.

Follow the instructions below to install Serial Converter device drivers from a disk:

• After inserting the CD into the disk drive, connect the USB Serial Converter to an open USB port.
• The “ Found New Hardware Wizard ” should run automatically, and will guide users through the remaining installation.
• Once prompted to connect with Windows Updates (which will ask to search for available drivers), choose the “ No, not at this time ” option.
• Follow all instructions to complete driver installation using the provided CD.
• ○ Under “Ports (COM & LPT)”, the device will be labeled as “ USB Serial Port (COMx) ”

• If drivers haven’t been installed correctly, a yellow exclamation icon is displayed under the “Ports (COM & LPT)” or “USB Serial Bus Controllers” menu.
• To fix any issues with installation: right-click the yellow exclamation icon, click “ Update Driver ”, and then search for the necessary driver (located on the disk provided with the USB Serial Converter).

How to change COM port settings in Windows 10

Some software applications are designed to only operate with designated serial ports. If you need to work with this kind of program, you may need to know how to find port numbers in Windows 10 so you can modify them if necessary.

In many cases when working with older devices or applications, you will be called upon to change COM port numbers to successfully operate the programs and peripherals. Some legacy equipment is only capable of working with specifically named serial ports.

The following procedure allows Windows users to change the COM port number for any attached device.

Just follow these simple steps on a Windows 10 machine to change the default COM port number.

• The Advanced Settings window is where you perform the number reassignment. You select an available port number from the list presented in the lower-left of the window. In our example, we are updating the device’s number from COM 3 to COM 5.
• Save the settings by clicking the OK button. This will close the open windows. The new number may not be assigned until the device is removed and reconnected to the computer.

Tip: Here is what you can try if COM ports are not showing in Device Manager:

• Open Control Panel.
• Search for “device” using the box in the top-right corner and select Device Manager from the results.

How to assign a COM port to a USB device Windows 10?

There are multiple scenarios in which you may need to assign a COM port to a USB device on your Windows 10 computer. Some devices need to have a COM port identifier that falls within a certain range, say between COM1 and COM4. Windows may have assigned a different identifier to the port which you will be required to modify. It’s a relatively simple procedure to perform.

Here is how to assign a COM port to a USB device Windows 10:

• Open the Windows Device Manager.
• Click on the Ports (COM & LPT) to expand the selection. You will see the ports currently in use along with their designated port identifier.

• Click on Port Settings and then click the Advanced button .
• Locate the COM Port Number at the lower left of the Advanced Settings window.
• Click the Com Port Number to change the currently assigned port identifier. Select the COM port identifier that you wish to assign to the USB device attached to the port.
• Click OK on all open Property windows.

Following these steps will enable you to change the COM port identifier for USB devices attached to your Windows 10 machine.

How to Reset com ports Windows 10

COM port (Communication port) is the title given to the port serial interface that’s located in a common (IBM compatible) computer.

There are occasions when computers offer users one or two physical COM ports (RS-232), but today's models usually lack these physical COM ports. It should be known that COM ports don’t always refer to physical ports. Virtual ports are available as well. These ports are developed when a USB-to-UART adapter is used—most often utilized by FTDI and Croduino.

See below for multiple examples of such devices (AKA cell phones, USB modems, RFID readers, card readers, etc.)

In each instance where Windows registers a new device (one which possesses a new ID), Windows connects that device to an empty port, from COM 1 port if you didn’t have any connections before, then (COM2, COM3, COM4, ​​etc.—from 1 to 255).

Additionally, every port is exclusively assigned to a single device, remaining occupied (Windows displays the COM port as “in use”) even when the device isn’t connected anymore.

For a majority of the time, this isn’t an issue unless users attempt to run certain legacy software (software that struggles to function with COM-ports higher than 9.)

One example is when an app functions effectively with COM1 to 9, but fails if no unoccupied COM ports below COM10 are available.

Another problem can occur when certain devices require far too many COM ports to function.

Specific adapters could reserve up to 30 (or more) COM ports. This situation means users are forced to delete COM ports being used in Windows—or switch a currently occupied COM port to a different device.

The tutorial below will explain how to clear currently occupied COM ports, as well as how to disable the numbering of new ports.

• Step 1: Hit Win+R (write regedit then click Enter).
• Step 2: Search through folders: HKEY_LOCAL_MACHINE\SYSTEM\CurrentConstrolSet\Control\COM Name Arbiter .

Note: This opens a window displaying port addresses.

• Step 4: Enter all zeros to reset.

What is USB serial port driver FTDI

Virtual COM port (VCP) drivers make USB devices appear as additional COM ports that the PC can access. USB devices can be accessed by application software similarly to how it would access standard COM ports.

Future Technology Devices International Limited’s software is offered “as is”. Any and all described (or implied) warranties (including, but not limited to, implied warranties of merchantability and fitness for a particular purpose) are disclaimed.

In no event shall Future Technology Devices International Limited be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused, and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.

FTDI drivers can be used only in conjunction with products based on FTDI parts.

Frequently Asked Questions

How to find device manager on windows 10.

• Using Windows Search The easiest way is to use the default Windows search bar located next to the Start Menu on the toolbar. Simply start typing “Device Manager” into the search field and it will be located for you with an easy “Open” link to access it.
• Open the Control Panel on your computer.
• Locate the “View By” option in the top right of the “Control Panel” screen.
• Select “Large icons” or “Small icons” according to your preference.
• “Device Manager” will be listed - all icons are ordered alphabetically in ascending order.
• From the WinX menu There are two ways to access the WinX menu. Either right-click on the “Start” menu or you can press Windows + X keys on the keyboard at the same time. Device Manager will be listed as an option in the menu that appears.
• devmgmt.msc
• mmc devmgmt.msc
• control hdwwiz.cpl
• From the Computer Management Console You can access the Device Manager from the Computer Management Console. Device Manager will be listed in the left panel under System Tools.

How to find COM port number on Windows 10?

• If the details of your COM ports are not visible in the Device Manager, open Device Manager and click on “Action” from the menu bar.
• Select the “Add legacy hardware” option, then click Next.
• Choose the “Install the hardware that I manually select from a list (Advanced)” option, and click Next.
• When complete, the “Ports (COM & LPT)” group will be listed in the Device Manager. Expand the group to view your device. The port along with the port number ie. Communications Port (COM4) will be displayed accordingly.

How to install a serial port driver?

• Download Virtual Serial Port Driver
• Double click to launch the application. If you see a User Account Control message, click “Yes” to allow the application to be installed.
• Follow the steps in the installation wizard. Read and accept the License Agreement, and click Next to continue.

Can't open the serial(com) port, What to do?

• Number 1: Connection to com1 Windows 10, com3 wouldn’t open. This issue sometimes occurs if users lack the required drivers. Solve this problem by updating the serial port driver, then verify the issue was resolved.
• Number 2: Putty can’t open Windows 10 serial port. This can happen because of certain Windows services. Resolve this issue by disabling these services.
• Number 3: Access to the serial interface com1 cannot be opened – This problem may occur due to problems with the serial interface. Resolve the problem by temporarily disabling the serial port
• Number 4: Com ports can’t open win error code 5, 123, 32. These are very common issues that often occur with a serial port Resolve most of these problems with one of our solutions

• COM Port on Windows 10

Manage COM Port Assignment in Windows 10

This question was asked by Praxair and answered by Brendan3385 but the solution given was product specific and did not solve the issue by modifying Windows 10. That is the type of solution I need.

REF: Windows 10 assign specific COM port to device

I am using digital calipers, Tesa micro heights, and other peripheral measurement devices, running through Midwest flexports with 25 pin serial to USB cables. These run to Dell Optiplex 3070 thin clients into an application called WINSPC.

WINSPC requires specifying the COM port in the application. Windows 10 self manages the assignment of COM ports. It frequently changes this assignment when rebooted or the serial to USB cable is unplugged. When it assigns a different COM port the measurement devices lose the ability to transmit data. I know I can change this manually in device manager every time as an admin but my users can not. I need to stop it from happening.

My ideas are possibly a registry edit, a locally placed startup script, or even a script attached to the profile in active directory.

I will need to frequently solve these types of issues throughout my career so if possible I would rather be taught to fish rather than find one in my desk drawer…

Thanks Everyone!

@lauren7060 @marcmaehner7836 @brendanshreve7169 @pblais

I use a USB Serial Port to access CLI on a Cisco ASA. But, if you open up Device Manager, right-click on device, port settings, advanced. There’s a number of settings, including the COM Port assignment. I quickly tested that assigning to 9, then moving around to different USB slots came up with same COM Port.

As far as Regedit goes, you might check \HKLM\HARDWARE\DEVICEMAP\ - in my case, \SERIALCOMM for the specific setting of COM9 as the example.

Is your thin client connecting to a VM or a RDS Session Host?

This article may be of some assistance. If you can find somewhere to view/update the serial numbers from each device, it should in theory always keep that COM port.

I’m going to look into this on some of our machines here to see if I can replicate this issue.

According to experience before, the Windows assign the COM port according VID, PID and serial number. So with the same device plug in, it should always get same COM port assignment. However, two devices with same VID, PID and serial number might be treated as same device. When you plug in them in sequence, Windows can assign different COM port for them. However, after rebooting the Windows with the two USB devices attached, the COM port assignment should be decided by Windows for the two USB devices with same VID, PID and serial number.

It is connecting to an RDS session.

Der Geist , Thank you, I tried doing what you did by selecting a COM port ( #9 ) that was unlikely to be used by Windows 10. Rather than fight Windows 10 over the COM3 or COM4 slots I sort of harmonized with it by allowing it to have the ability to allocate (manage) the first few (usable) ports as, or if, things get plugged/unplugged and I assigned it to something that should never be used like COM9. After several tests of unplugging rebooting etc… it continues to assign it to COM9

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How to check COM ports in Windows 10?

Just like we can check COM ports in windows 7 or lower , by going to

Control Panel >> Device Manager >> Ports

How should we check it in Windows 10?

• 2 By going to device manager? What makes you think it changed? You could do this in Windows 8 and Windows 8.1 –  Ramhound Commented Mar 31, 2016 at 2:50
• 4 It's in exactly the same place. Just checked. Downvote: Little research effort. (Darn, the assoc bonus is only 100) –  SIGSTACKFAULT Commented Dec 16, 2016 at 14:58
• 1 @Ramhound: By seeing the change. –  Mahmood Dehghan Commented Jan 31, 2017 at 18:31
• 2 Still not answered for me. The ports do not show up even as hidden devices. This may be a policy issue. –  benJephunneh Commented Feb 28, 2019 at 16:40
• 1 Definitely not there on my Windows 10. –  Turkeyphant Commented Aug 17, 2020 at 17:01

3 Answers 3

I had the same question and I found this page. And the answer is in @zipzit's comment. So I post it as answer here:

To see "Com Ports" in Device Manager in Windows 10 you should select "Show hidden devices" in View menu.

• 7 still not visible –  Blue Clouds Commented Sep 23, 2018 at 4:53
• 1 @BlueClouds maybe it is shown as Ports (COM & LPT) –  Mahmood Dehghan Commented Sep 23, 2018 at 8:24
• 2 Nope, Ports not shown even after "Show hidden devices". –  Klitos Kyriacou Commented Jul 19, 2020 at 11:03
• Same here, no Ports shown after "Show hidden devices". –  Turkeyphant Commented Aug 17, 2020 at 16:58

The Device Manager still exists in Windows 10 and should show this. It has not really changed at all between versions.

Open your Start Menu and just type in Device Manager , and it will come up.

• 9 Device manager is just fine. But that's not the question. Where are the COM ports called out? I can't see them in Win10... Oops... found them. Device manager has a thing "View Hidden Devices" You have to specifically select that before the Ports (COM & LPT) are even visible. –  zipzit Commented Oct 26, 2016 at 3:00
• The proper path to Device Manager is: Open RESOURCE EXPLORER (Win+E), right click on THIS COMPUTER, click on DEVICE MANAGER Anyway on my Windows 10 the number of each port is NOT shown here. –  jumpjack Commented May 8, 2017 at 7:07
• @jumpjack Why do you think that is the "proper path"? What about Win-R, devmgmt.msc ? –  Jamie Hanrahan Commented May 31, 2017 at 22:28
• The win+R is a shortcut for advanced users knowing what an executable is. A standard user "just clicks". :-) –  jumpjack Commented Jun 8, 2017 at 7:34
• 3 Even easier is Win+x, m. –  benJephunneh Commented Feb 28, 2019 at 16:44

I am using Windows 10 21H2 and before @Mahmood Dehghan's answer, I had to go to Device Manager's "Advanced" menu and "add legacy hardware" for communication ports. Then the View->"Show hidden devices" answer would work.

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Finding & Removing Hidden COM Ports

Finding & Removing Hidden COM ports for Non-connected Devices in Windows XP (this procedure also works for Windows 7 & 10)

Thanks to Jack, KF6T, Rick, N6XI, Ward, N0AX, and Steve, N2IC, as sources for the information on this page.  Since ham radio operators use COM ports to communicate with various devices in their stations, there may be a time when you need to clean out old and unused COM port assignments which were created, but not deleted, by Windows XP.  This may be useful if you have problems installing new COM port devices such as USB Serial Adapters or legacy serial ports.  Or when installing COM devices, Windows assigns higher COM port numbers such as COM18, etc.  In most cases, you can over-ride the port number that Windows assigns by going to the Properties of the device in Device Manager , then to the Port Settings tab and click on the Advanced button.  Or by using one of the two procedures below, you can eliminate old and unused COM ports to free up resources for devices you already have installed and wish to move to a lower port number or for devices you wish to install in the future.

Two procedures are shown below.  The first one is a permanent solution where all hidden devices (including COM ports) will be shown each time  Show Hidden Devices is enabled in the View menu of Device Manager . The second procedure is for showing all hidden devices on a temporary basis and includes how to delete hidden COM ports to free up resources. I’ve performed both procedures on both my shack computers where old assignments of COM ports remained for devices I no longer use.  I am now set for the permanent solution.   Both procedures are outlined by Microsoft at http://support.microsoft.com/kb/315539 .

Procedure for Permanent Fix to Finding Hidden Devices in Device Manager

1. Right click on My Computer then go to Properties .

9. To delete a particular port, click to highlight it and hit the Delete key on your keyboard.  In the Confirm Device Removal dialog box, click OK .

10. After you have deleted the unused and hidden COM ports, the list will show only those COM ports you use or may use in the future (during the procedure, you may have to scroll back down Device Manager to get back to the Ports section.) Notice I kept the unused COM6 for my Keyspan USB Serial Adapter even though it is not connected and not being used at the moment.  When I connect my Keyspan adapter, it always comes up COM6 now which is what I want.

Procedure for Temporarily Finding Hidden Devices in Device Manager

1. COM ports assignments can be viewed from the Windows Device Manager .  There are a couple of ways to get to the Device Manager .  The easiest way, if you have a My Computer icon on your desktop, is to right-click My Computer and go to Properties .  The other way is to go to theStart | Control Panel | System | Hardware | Device Manager.

2. When the Systems Properties dialog window opens, click on the Hardware tab.

3. On the Hardware tab, click on the Device Manager button.

4. In Device Manager , click the + sign next to Ports (COM & LPT) to reveal what ports are currently in use.

5. You will notice if you go to the View menu in Device Manager and click on Show hidden devices , that nothing changes in your Ports list.

6. To view actual hidden COM ports, close Device Manager .  Go to Start > Run .

7. When the Run dialog box opens, type cmd.exe and hit enter or click OK .

8. When the cmd window opens, type set devmgr_show_nonpresent_devices=1 then hit Enter .

9. Then open Device Manager from the cmd window by typing start devmgmt.msc and hit Enter . (Note, if Device Manager does not open when you start devmgmt.msc , then type cd\windows\system32 and hit Enter, then type start devmgmt.msc and hit Enter .)

10. When Device Manager opens, go to the view menu and click Show hidden devices (same as Step #5 above).  Scroll down to the Ports section and you will be able to see all the hidden COM ports.  In this particular example, there are seven hidden COM ports showing on my main shack desktop computer.  Of these seven, six are for devices I no longer use.  I occasionally use the Keyspan port showing as (COM6) so decided to keep it.

11. To delete a particular port, click to highlight it and hit the Delete key on your keyboard.  In the Confirm Device Removal dialog box, click OK .

12. After you have deleted the unused and hidden COM ports, the list will show only those COM ports you use or may use in the future (during the procedure, you may have to scroll back down Device Manager to get back to the Ports section.) Notice I kept the unused COM6 for my Keyspan USB Serial Adapter even though it is not connected and not being used at the moment.  When I connect my Keyspan adapter, it always comes up COM6 now which is what I want.

13. When finished, close Device Manager .  To close the cmd window, type EXIT and hit Enter .  The box will close.

Note that any time you close the cmd window, you lose the context that permits Device Manager to display and manage COM ports for non-connected devices.  To check again, you have to perform the procedure over or else use the permanent fix on the Microsoft webpage listed at the beginning of this page.  On my laptop, I tried to delete unused Bluetooth COM ports that were assigned the same port numbers as my USB serial adapter.  After a reboot, these Bluetooth COM ports returned to the hidden list even though they were not being used.  The only problem it poses is when I disconnect my USB serial adapter and then reconnect it.  Windows may assign different COM ports numbers than what I previously used and have been assigned in my software.  There are 64 COM ports showing on my XP laptop because of Bluetooth.  So far, this hasn’t caused any conflicts that I am aware of.

Last update on February 21, 2024

Find COM port number in Windows 10 – fast and simple method

Understanding how to find the COM port number in Windows 10 is essential when working with devices that connect through a system’s serial ports , such as modems, barcode scanners, and various industrial equipment. Identifying the correct COM port is the foundation for establishing a successful communication link between your computer and external devices. In this article, I share my personal experience and methods to locate the COM port number , ensuring you can configure your hardware without hitches. For more in-depth guidance on Windows device management, visit Microsoft Support .

Common Scenarios:

Finding your device’s port number 🔎.

• Sometimes when installing a new device, you may need to know its COM port number for proper setup.
• Troubleshooting communication issues between your computer and a serial device often requires you to check the assigned COM port .
• Software development involving serial communication necessitates knowing the COM port to test code and interactions with hardware.

Setting Up Industrial Equipment 🔩

• Industrial equipment often uses RS-232 or RS-485 interfaces , which require the correct COM port setting to function.
• In situations where multiple serial devices are connected, identifying each specific COM port becomes critical.

Programming Microcontrollers 💻

• When programming devices such as Arduino or Raspberry Pi , you must identify the proper COM port to upload your sketches or communicate with the board.
• Serial port monitors and other development tools need the correct COM port information to capture data transmitted between the computer and microcontroller.

Step-by-Step Guide. Com Port On Windows 10, Virtual Serial Port:

Method 1: device manager 🔍.

• Press Windows Key + X and select Device Manager from the menu.
• Expand the ‘Ports (COM & LPT)’ section to reveal a list of COM ports in use.
• Note the COM port number assigned to your device, usually indicated in parentheses (e.g., COM3).

Note: If the device is not properly installed or recognized, it may appear under ‘Other devices’ or with a yellow exclamation mark.

Conclusion: Device Manager is the most direct method to find the assigned COM port in Windows 10.

Method 2: Using Command Prompt 🗣

• Open Command Prompt by typing ‘cmd’ in the Start menu search bar and selecting it.
• Type the command mode and press Enter to list all active COM ports.
• Look for devices listed under ‘Devices’ to find their respective COM port numbers.

Note: This method provides a quick, command-line based overview of COM ports.

Conclusion: The mode command is useful for users comfortable working with the Command Prompt interface.

Method 3: PowerShell 📖

• Access PowerShell by right-clicking the Windows Start button and selecting ‘Windows PowerShell’.
• Type Get-WmiObject Win32_SerialPort | Select-Object Name, DeviceID and press Enter .
• The output will display the device name and COM port; the DeviceID is the COM port number.

Note: PowerShell provides a powerful alternative to Command Prompt for advanced users.

Conclusion: PowerShell scripts offer a versatile option for automating COM port identification tasks.

Method 4: Third-Party Software 🔌

• Download and install a third-party utility like MajorGeeks that allows you to manage and monitor COM ports.
• Run the software and navigate to the section displaying serial ports .
• Locate your device and note the COM port number provided by the software.

Note: While convenient, ensure the software is from a reputable source to avoid security risks.

Conclusion: Third-party software can offer enhanced features and a more user-friendly interface for detecting COM port numbers.

Method 5: BIOS/UEFI Settings 🏷

• Reboot your PC and enter the BIOS/UEFI settings , usually by pressing a key like F2, Delete , or Esc during startup.
• Navigate to the ‘Peripherals’ or ‘Advanced’ section to find serial port configurations.
• Note the designated COM port if available; often this is relevant for on-board serial ports.

Note: Not all computers display COM port information in the BIOS/UEFI, especially for USB-connected devices.

Conclusion: Checking the BIOS/UEFI is more about configuring built-in serial ports rather than finding the COM port for external devices.

Precautions and Tips:

Navigating device manager 📚.

• When using Device Manager , always refresh the view if you’ve recently connected a device to update the COM port listing.
• Devices may be listed under generic names; look for the port number to ensure accuracy.

Additional Insights for Managing COM Ports

Managing COM ports on a Windows 10 system can at first seem daunting to the uninitiated. However, by following the methods detailed above, you can confidently identify and configure your COM port settings. It’s worth mentioning that modern Windows systems are designed to automatically handle COM port assignments, so manual intervention is usually only necessary for specific use cases or troubleshooting purposes.

Additionally, if you use virtual machines or remote desktop services , it’s important to understand that COM port mappings can vary across different environments. You may need to set up port redirection to maintain consistent COM port numbers when working in these scenarios, which is commonly done through the software settings of virtual machines like VMware or Remote Desktop Services .

Conclusion:

Identifying the correct COM port number is crucial for seamless interaction with serial devices. Regardless of your level of expertise, one of the outlined methods should suit your needs and allow you to complete the task efficiently. Whether you’re working in an industrial setting, developing software, or setting up a simple peripheral, knowing how to find the COM port number will save you time and potential frustration. For additional resources on managing and troubleshooting serial connections, you can visit Microsoft Support .

How can I view available COM ports on Windows 10 ?

To see available COM ports , open Device Manager , expand the 'Ports (COM & LPT)' section, and the assigned COM ports will be listed.

Is it possible to create a virtual serial port in Windows 10 ?

Yes, you can create a virtual serial port using third-party software like Virtual Serial Port Driver.

What are virtual COM port drivers used for?

Virtual COM port drivers enable software applications to communicate with hardware devices via a USB port as though it were a serial interface.

Can I emulate multiple COM ports on Windows 10 simultaneously?

With specialized software, you can emulate multiple COM ports simultaneously to enable the operation of several serial applications.

How do I assign a specific COM port number to a device in Windows 10 ?

In Device Manager under 'Ports (COM & LPT)', right-click on your device, choose 'Properties', go to 'Port Settings' and then 'Advanced' to set a desired COM number.

What might cause a COM port to stop working in Windows 10 ?

COM port issues can stem from outdated drivers, hardware conflicts, or incorrect configuration settings.

How can I troubleshoot a COM port that is not responding?

Verify the COM port's settings in Device Manager , update drivers, check cable connections, and ensure the device is powered on.

What should I do if I don't see any COM ports in Device Manager on Windows 10 ?

You might need to reveal hidden devices in Device Manager or add a COM port manually using the 'Add legacy hardware' wizard.

Do I need administrative rights to add, remove, or configure a COM port in Windows 10 ?

Administrative rights are typically necessary to manage hardware settings, including adding or configuring COM ports .

Is it possible to use Bluetooth devices as COM ports in Windows 10 ?

Windows 10 can map Bluetooth devices to COM ports through the Bluetooth settings 'More Bluetooth Options' and configuring the 'COM Ports' tab.

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How to change asynchronous serial COM port assignments in Windows Device Manager

Sealevel recommends using the installed COM numbers if at all possible to avoid system conflicts. If you previously installed a USB or PCMCIA serial interface, it will have resources assigned by the operating system. If the device is not currently connected to your computer, these COM assignments will not be apparent and forcing new COM port assignments will create a conflict when the devices are reconnected at a later time.

One scenario where you would have to change the COM port assignments is when your legacy application only works at COM1 through COM4 and the Sealevel serial device you installed comes in at COM5 or higher. Another scenario might occur when you install a multiport serial card and the COM port numbers are not assigned consecutively and you want them to appear consecutive.

In Windows 7, Vista, XP or 2000 operating systems, you can change the COM number assignment using Windows Device Manager.  To change the COM port assignments in Device Manager, follow these basic steps:

1) Click the Start button.

2) Right-click on My Computer.

3) In the fly-out menu, click Manage.

4) In the Computer Management Window, click on Device Manager.

5) In the right-hand pane, expand the Ports (COM & LPT) listing by clicking the “+” symbol.

6) Right-click on the COM number you want to change and select Properties from the fly-out menu.

7) In the Communications Port Properties window, click the Port Settings tab and then click the Advanced button.

8) In the Advanced Settings window, you can select the new COM port number from the drop box (be careful not to select a COM number already in use).

9) Click the OK button to confirm your changes. If Windows detects a conflict, choose another COM port number.

10) Click the OK button to close the Communications Port Properties window.

11) When Device Manager refreshes the hardware list, the COM assignment will reflect your changes. To get Device Manager to refresh the window on Windows XP, you may need to click ‘Action’ in the menu and then click ‘Scan for hardware changes’ in the sub-menu (Note: If ‘Scan for hardware changes’ isn’t listed in the sub-menu, click on the computer name in the right pane and then repeat this step).

Contact our technical support department if you are still experiencing problems with serial COM port assignments.

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Resetting Windows COM Ports

Here are instructions helps ECE 3520 students that are having issues with COM ports using the STK 500.

What is a COM port?

COM port (Communication port) is the name for the port serial interface that can be found in a common computer(IBM compatible). Sometimes computers come with one or two physical COM ports (RS-232), while today's models don't have them ususally. However, the COM port does not necessarily refer to physical ports, but also virtual. Such ports are created when using USB-to-UART adapter, most notably used by FTDI and Croduino. Here are a few examples of such devices: USB modems, cell phones, RFID readers, card readers, and so on.

Every time Windows register such a device with a new ID, it gives that device a new COM port (COM2, COM3, COM4, ​​etc.). Even when you turn off the device, the COM port that is assigned to the device remains reserved for it. That is, each time you reconnect they will be assigned to the same COM port. Generally it's great. The problem can occur if some software that comes into your device is set so that it can access only, say, the first nine COM ports. However, this tutorial will describe how to "clean" COM ports that are in use, and how to disable numbering of new ports.

How reset COM Ports.

Use one of the two methods to reset the COM ports on your Windows computer.

• Click start –> Run –> type regedit and click OK button.
• Registry editor will open.
• Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter
• In the right panel , you'll see a key ComDB right click to that key and click modify.
• In value Data section select all and delete reset to Zero ‘0’.
• Close Registry editor and then restart your computer. All COM ports are now Free. You might need to reinstall any USB to serial convertor.
• Click go to Start, type devmgmt.msc in the Start Search box, and then press ENTER.
• In Device Manager, double click Ports (COM & LPT) to expand this section.
• Right click Communications Port (COM1) and then click Properties.
• Click Port Settings tab and then click Advanced… button.
• Pull down COM Port Number list, choose one of the com port in use and then click OK.
• When a warning message occurs, please ignore it and click Yes directly.
• Please repeat step 3 to 7 to choose another com port in use. Once the above steps are completed, please change the port back to original (COM1) setting.

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how to assign static COM port number to a device

I have an issue with one device ( Pax Technology Terminal ) connected to Win 10 ( NCR Point of Sale ). after unplugging the device and connecting it the COM port number changes and every time we have to change the port number back to the correct port number for this device to work.

Is there way I set this device to only get a certain COM port number every time they unplug and connect it back ?? something like setting defaults for each device type

Windows 10 A Microsoft operating system that runs on personal computers and tablets. 11,364 questions Sign in to follow Follow

Dear all USB Users, (unsure that this is the right forum for my question...)

Is there a way to programmatically "Recover Unused and FIX COM Numbers" (NI - National Instrument Forum Question...)

It is hard to live with the Totally Random USB COM port Enumeration that Windows always apply... Is there a way to make this less Random, or even totally controlled and pre-visible?

I found that for each USB device the following apply (or at least should apply) Each device has:

• VID = Vendor ID
• PID = Product ID
• PSN = Product Serial Number So with we have the possibility to make a COM-Port-Number Reservation/Binding Option for this USB device with Unique ID: VID&PID&PSN This would result in the possibility for having the desired Unique Fixed COMxx Port Number Reservation...

See my proposal in the attached TXT document... 269324-windows-usb-com-port-enumeration-problem.txt

The Simple Solution to this Problem could be just like **DHCP MAC-Address to IP-Address binding... Like VID&PID&PSN to COMxx Port Binding forever on this computer...

Thanks... The World and I would appreciate a COMMENT to this... And much better also an action to this problem...!

Thank you for reading ana all the best regards Ronn

I encountered similar issue. When the COM number is assignated and confirmed, Device Manager is closed automatically and the COM number remains unaffected.

Windows manages the COM port number assignments, and a device's COM port number may change after a reboot.

To manually change the COM port number of a device:

• Open Windows Device Manager > right click the device > Properties
• Under Port tab > Advanced
• Change COM port number

Also, according to the experience before, the Windows assign the COM port according VID, PID and serial number. So with the same device plug in, it should always get same COM port assignment. But when two devices with same VID, PID and serial number might be treated as same device. When you plug in them in sequence, Windows can assign different COM port for them. However, after rebooting the Windows with the two USB devices attached, the COM port assignment should be decided by Windows for the two USB devices with same VID, PID and serial number.

-------------------------------------------------------------------------------------

If the Answer is helpful, please click " Accept Answer " and upvote it.

How can ANY two devices have the same serial numbers ??

How to Check COM Port in Windows 10: A Step-by-Step Guide

Checking your COM port in Windows 10 is like finding a hidden treasure in your computer. It’s the way your computer talks to all sorts of devices like printers and modems. Don’t worry, it’s not as complicated as it sounds. In just a few quick steps, you’ll be chatting with your devices like old friends.

Step by Step Tutorial: How to Check COM Port in Windows 10

Before we dive into the steps, let’s understand what we’re trying to achieve here. This tutorial will guide you on how to locate and identify the COM ports on your Windows 10 computer. These steps are essential, especially if you’re troubleshooting device connection issues.

Step 1: Open Device Manager

Hit the Windows key, type "Device Manager," and click on the result.

The Device Manager is like the control center for all the hardware attached to your computer. It’s where you can peek under the hood and see all the nitty-gritty details.

Step 2: Expand the "Ports (COM & LPT)" section

Click on the little arrow next to "Ports (COM & LPT)" to see a list of COM ports.

You might see a few different COM ports listed here. Each one represents a different way your computer can talk to external devices. It’s like having different doors in your house for different guests.

Step 3: Identify the COM Port

Look for the device you’re interested in and note the COM port number assigned to it.

This is where you find out which door your special guest (the device) will be using. The COM port number is like the address for that door.

After you complete these steps, you’ll know exactly where to look the next time you need to check your COM ports. It’s a handy bit of knowledge that can save you a lot of headaches down the road.

Tips: Navigating COM Ports in Windows 10

• If the device you’re looking for isn’t listed, try unplugging it and plugging it back in.
• Sometimes, devices might be under a different name, so make sure to look carefully.
• If you can’t find the "Ports (COM & LPT)" section, you may need to install drivers for your device.
• Keep your Device Manager organized by regularly checking for devices you no longer use and uninstalling them.
• Remember to always safely eject your devices before unplugging them to avoid any damage.

Frequently Asked Questions

What is a com port.

A COM port is a communication port on your computer that lets it talk to external devices like modems and printers.

Why do I need to check my COM port?

Checking your COM port is important for troubleshooting connection issues with external devices.

Can COM port numbers change?

Yes, COM port numbers can change, especially if you plug the device into a different USB port.

What if my device isn’t listed under "Ports (COM & LPT)"?

If your device isn’t listed, it might be under a different section, or you may need to install the necessary drivers.

How do I know if my COM port is working correctly?

If your COM port is working correctly, your device will communicate with your computer without any issues.

• Open Device Manager.
• Expand "Ports (COM & LPT)" section.
• Identify the COM port number.

So, there we have it – a simple guide on how to check COM port in Windows 10. As you can see, it’s not rocket science, just a few clicks and you’re there. Knowing how to navigate through the Device Manager and identify your COM ports is a useful skill that can help you in many situations, especially when dealing with device connectivity issues. Remember to always keep your drivers updated and to safely manage your devices to avoid any mishaps. If you ever find yourself stuck or confused, return to this article or reach out to tech-savvy friends or professionals for help. Happy computing, and may your devices always connect smoothly!

Matt Jacobs has been working as an IT consultant for small businesses since receiving his Master’s degree in 2003. While he still does some consulting work, his primary focus now is on creating technology support content for SupportYourTech.com.

His work can be found on many websites and focuses on topics such as Microsoft Office, Apple devices, Android devices, Photoshop, and more.

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How to change the COM port for a USB Serial adapter on Windows 7, 8, 8.1, and 10

Originally authored by: Bernie Thompson, July 4, 2011

Start by going to the Device Manager. Once there do the following: Expand the Ports ‘(COM& LPT)’

You should be looking at something like this:

As you can see Windows has set the port to COM10. However many legacy applications expect the port to be between 1-4. Let’s change that:Right click on the device and click on ‘Properties’.

Click on ‘Port Settings’. Then click on ‘Advanced…’.

Once you’re in ‘Advanced Settings for COM10’ on the bottom you can see the ‘COM Port Number: COM10’. Click on that to change it to the lowest possible number (between 1-4).

Then click ‘OK’ on all open Property Windows. Now the device should look like this:

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How to assign a COM port number?

We are using a USB-to-Serial converter. Windows assigns a COM port number to the serial device. For testing purposes, we need to control the COM port number assigned by Windows. For example, we would like to tell Windows to assign COM 255 to a device rather than have Windows decide what the number is. Is there any way to do this?

• serial-port

• 1 Assign it programmatically ? if so, what language ? otherwise, you can do it from Device Manager in Windows. –  Nasreddine Commented Nov 17, 2011 at 15:40
• 1 This is the most odd test requirement I've seen in awhile... –  Brad Commented Nov 17, 2011 at 15:41
• 1 It is up to the driver, not Windows. Finding a converter with a driver that lets you do this is going to be hard shopping. The odds that your user will have one are even smaller. –  Hans Passant Commented Nov 17, 2011 at 15:48

3 Answers 3

I do not have to do this programmatically, so Nacereddine is right. My Computer -> Manage -> Device Manager -> Ports -> Communications Port -> Port Settings -> Advanced -> COM Port Number

• 1 My answer basically said the same thing, but without as much detail because the details depend on the driver. If you are going to accept your own answer which says almost the same thing you should specify the device make/model so that people understand that your answer might be specific to that make/model. –  Shane Wealti Commented Nov 23, 2011 at 0:53

This normally depends on the driver. Some drivers allow you to edit the COM port number assigned by going into the device properties in device manager and using one of the properties pages to specify the COM port number. If the model you are currently using doesn't support this I suggest finding a model that does.

No, but if you know what device id it reports to the OS then its possible that you could find it programmatically in the device manager.

Here's a link to a code project that may give you some ideas.

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How to Allow Ports Through Firewall Windows 10: A Step-by-Step Guide

Allowing ports through a firewall on Windows 10 can seem tricky, but it’s actually pretty straightforward once you know what to do. This guide will walk you through the process step-by-step so you can get your ports opened up quickly and easily.

How to Allow Ports Through Firewall on Windows 10

These steps will show you how to allow ports through your firewall on a Windows 10 computer. This is useful for enabling certain applications or services that need specific ports to function correctly.

Step 1: Open the Windows Firewall

First, navigate to your Control Panel by clicking on the Start Menu and searching for "Control Panel."

Once you’re in the Control Panel, find and click on "System and Security." From there, click on "Windows Defender Firewall."

Step 2: Advanced Settings

Next, you need to access the advanced settings.

In the left-hand pane, click on "Advanced settings." This will open the Windows Firewall with Advanced Security window.

Step 3: Inbound Rules

Now, you need to create a new rule to allow the port.

In the left-hand pane, click on "Inbound Rules." Then, in the right-hand pane, click on "New Rule…"

Step 4: Select Port

In the New Inbound Rule Wizard, select "Port" and click "Next."

This screen asks what type of rule you want to create. By selecting "Port," you’re specifying that the rule will control network traffic on a specific port.

Step 5: Specify Port Number

Choose whether the rule applies to TCP or UDP, then enter the specific port number you want to allow. Click "Next."

Make sure you know whether your application uses TCP or UDP, as this is crucial for the rule to work correctly. If you’re unsure, refer to the application’s documentation.

Step 6: Allow the Connection

Choose "Allow the connection" and click "Next."

By selecting this option, you’re telling the firewall to let the traffic through on the specified port.

Step 7: Profile Selection

Select when the rule applies by choosing the network locations (Domain, Private, Public). Click "Next."

Typically, you would select all three to ensure the rule applies no matter where you connect your device.

Step 8: Name the Rule

Give your new rule a name and click "Finish."

A descriptive name will help you remember what this rule is for in case you need to modify or delete it later.

After completing these steps, your specified port will be open, allowing the related application or service to function correctly.

Tips for Allowing Ports Through Firewall on Windows 10

• Know Your Ports: Make sure you know which ports your application or service needs.
• Double-Check: Ensure you correctly select TCP or UDP as required by your application.
• Use Descriptive Names: Naming your rules clearly helps with future management.
• Security: Only open ports you absolutely need to reduce security risks.
• Documentation: Always refer to the specific app’s documentation for any additional settings or requirements.

Frequently Asked Questions

What is a firewall.

A firewall is a security system that protects your computer by controlling incoming and outgoing network traffic based on predetermined security rules.

Why do I need to allow ports through the firewall?

Certain applications or services need specific ports to be open to communicate with other devices or servers effectively.

What’s the difference between TCP and UDP?

TCP (Transmission Control Protocol) is connection-oriented, ensuring data is delivered in order. UDP (User Datagram Protocol) is connectionless, faster but less reliable.

Is it safe to open ports?

Opening ports can expose your computer to potential security risks, so only open ports you absolutely need and make sure your system is otherwise secure.

Can I close a port after opening it?

Yes, you can go back into the Windows Firewall with Advanced Security and disable or delete the rule you created.

• Open the Windows Firewall.
• Go to Advanced Settings.
• Click Inbound Rules.
• Select Port.
• Specify Port Number.
• Allow the Connection.
• Select Profile.
• Name the Rule.

Allowing ports through a firewall on Windows 10 might seem daunting at first glance, but with the right steps, it’s a manageable task. By following the outlined steps, you ensure that your applications and services can function without hiccups, while maintaining control over your network security. Remember, always be cautious about which ports you open, as each one can be a potential entry point for malicious activity. If you aren’t sure, consult with someone knowledgeable or refer to the application’s documentation. Keep exploring and learning more about your computer’s security settings to stay protected. If you found this guide helpful, consider sharing it with others who might benefit from it.

Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.

He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.

Read his full bio here .

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349 SE Thornhill Dr,   Port Saint Lucie, FL 34983

What's special.

Welcome to your dream oasis! Charming 3/2 solar powered home with an open concept living/dining room with an additional Florida room on this single-family home with no HOA. Beautifully maintained screened inground pool with ample shade and privacy for relaxing and entertainment. Feel at ease with a 2022 shingle roof, 2021 water heater and newer flooring and hurricane windows throughout the home. The kitchen includes newer stainless-steel appliances and a newer dish washer. Experience true Florida living while relaxing by your pool or take a ride to beautiful clear water beaches within 25 minutes or 5 minutes to local shopping centers and dining. Furniture is negotiable. Show more

Likely to sell faster than 96 % nearby

Travel times

Tour with a buyer’s agent.

We’ll find a local expert to take you on a private tour of 349 SE Thornhill Dr .

Next available tour time: Today at 2pm

Open houses.

12:00 PM - 2:00 PM

Facts & features

Bedrooms & bathrooms.

• Bedrooms : 3
• Bathrooms : 2
• Full bathrooms : 2
• Room types : Attic, Florida

Primary bedroom

• Dimensions : 19 x 11
• Dimensions : 12 x 10
• Dimensions : 12 x 12

Dining room

• Dimensions : 12 x 14
• Dimensions : 9 x 9

Living room

• Dimensions : 17 x 13
• Central, Electric, Solar
• Ceiling Fan(s), Central Air, Electric
• Included : Dishwasher, Dryer, Freezer, Ice Maker, Microwave, Electric Range, Refrigerator, Washer, Electric Water Heater
• Laundry : In Garage, Washer/Dryer Hookup
• Flooring : Carpet, Ceramic Tile, Laminate, Tile
• Windows : Impact Glass, Shutters, Panel Shutters (Partial), Impact Glass (Partial)

Interior area

• Total structure area : 2,040
• Total interior livable area : 1,536 sqft

Virtual tour

• View virtual tour
• Total spaces : 1
• Parking features : 2+ Spaces, Driveway, Garage - Attached
• Attached garage spaces : 1
• Has uncovered spaces : Yes
• Levels : 1.00
• Stories : 1
• Patio & porch : Covered Patio, Screened Patio
• Has private pool : Yes
• Pool features : Equipment Included, Gunite, In Ground, Screen Enclosure, Solar Heat
• Fencing : Fenced
• Has view : Yes
• View description : Pool
• Has water view : Yes
• Waterfront features : None
• Size : 10,000 sqft
• Features : < 1/4 Acre
• Residential vegetation : Fruit Tree(s)
• Additional structures : Shed(s)
• Parcel number : 342056013410009
• Zoning : RS-2 PSL

Construction

Type & style.

• Home type : SingleFamily
• Architectural style : Ranch,Traditional
• Property subtype : Single Family Residence
• Attached to another structure : Yes
• Frame, Stone
• Roof : Comp Shingle
• New construction : No
• Year built : 1984

Utilities & green energy

• Sewer : Public Sewer
• Water : Public
• Utilities for property : Cable Connected, Electricity Connected

Community & HOA

• Features : None, No Membership Avail
• Security : None, Smoke Detector(s)
• Subdivision : Port Saint Lucie Section 13
• Has HOA : No
• Services included : None
• Region : Port Saint Lucie

Financial & listing details

• Price per square foot : $286/sqft
• Tax assessed value : $269,900
• Annual tax amount : $5,111
• Date on market : 8/21/2024
• Listing terms : Cash,Conventional,FHA,VA Loan
• Electric utility on property : Yes
• Road surface type : Paved
• Saint Lucie County
• Port Saint Lucie
• Floresta Gardens
• 349 SE Thornhill Dr

Nearby cities

• Fort Pierce Real estate
• Jensen Beach Real estate
• Port Saint Lucie Real estate
• Saint Lucie Real estate

HOW TO: Remove Unused COM Ports for Re-assignment with Windows RealPort

This guide shows instructions on how to remove and change COM Port Assignments in Windows 7. Because the process requires you to enter the Device Manager, caution is advised .  

Show all Com Port Assignments

• Open a Command Prompt window, right click and select Run as administrator :

• Type the following lines:

•  In Device Manager: click View , then Show Hidden Devices .

• Expand the section labeled Ports (COM & LPT) to view all COM Ports that have ever been installed on this computer. COM Ports that have been assigned but are not currently connected will have a light-grey icon .

To remove an old COM Port

• Right-click on the COM Port in question and chose Uninstall.

To change COM Port assignments

• Expand the Multi-port serial adapters entry, right-click on the Digi device you want to change and chose Properties .
• In the Properties window, click the Advanced tab, followed by Properties .
• In the Advanced Properties window, click the desired port number on the left, then Serial .
• Chose an unused COM Port from the drop-down list and click Apply .

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