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Unable to install Virtual Port Driver
The problems described below may occur when creating a virtual COM port configuration.
A virtual port won't show up in the Ports group (COM and LPT).
The virtual devices created with our program appear in a separate group named Virtual Serial Port.
The virtual port is available, but it is labeled with an exclamation mark in Device Manager.
This problem may occur when you try to create a port with a number that already exists in the system. To resolve the issue, try creating a virtual port with the number COM20. If you need to create a port with an already existing number (for example, COM1), then follow these steps:
1.Close all programs that might use COM1.
2.Find COM1 in Device Manager.
3.Right-click on it.
4.Select Properties and go to the Port Settings tab.
6.In the COM Port Number drop-down list select a free port and click OK.
7.Wait until the operating system applies the changes in the port number. You may need to reboot your computer.
Fig. 1. COM port settings
Fig. 2. Selecting a new COM port number
Unable to create a COM port. A new device won't show up in Device Manager, or it is labeled as unknown.
This problem is due to a failure to install the virtual port driver. Our driver has a valid digital signature, and there should be no problem installing it on all supported versions of Windows, including 64-bit editions.
The driver can only be installed with administrator rights. Please make sure that your account has the appropriate permissions.
The operating system cannot verify the digital signature of the driver. This problem may occur on older operating systems when there is no Internet connection, and no updates installed. You need to update your operating system or install updated certificates using rootsupd.exe in the program folder.
For 64-bit Windows: c:\Program Files (x86)\Virtual Null Modem\inf\
For 32-bit Windows: c:\Program Files\Virtual Null Modem\inf\
In operating systems released later than Windows Vista or Windows Server 2012, your PC or server's security policy may prohibit installing the driver for all new devices or the selected device classes. Such a policy may be implemented at the organization level if your computer is connected to the domain.
The easiest way to check your security policy is to run the rsop.msc snap-in:
1.Use the Windows key + R shortcut.
2.Type rsop.msc and press Enter.
3.The snap-in will check the existing security policy and display the enabled rules.
4.You need to make sure that there are no prohibiting or restricting rules in the group policy:
Computer Configuration - Administrative Templates - System - Device Installation - Device Installation Restrictions.
•Prevent installation of removable devices.
•Prevent installation of devices not described by other policy settings.
Make sure you disable these settings during the installation of a new device. To change policy settings, contact your system administrator if necessary.
To configure policy settings, you can use the gpedit.msc snap-in.
Note: Group Policy Management Editor (gpedit.msc) is not installed by default in Starter, Home, and Home Premium editions. You will need to install it or use the registry editor.
1.Use the Windows key + R shortcut.
2.Type gpedit.msc and press Enter.
3.Go to Group Policy Editor: Computer Configuration - Administrative Templates - System - Device Installation - Device Installation Restrictions.
4.Disable the settings "Prevent installation of removable devices" and "Prevent installation of devices not described by other policy settings." Double-click on the name of the setting in the list and select Disabled.
5.In the program Virtual Null Modem, select System (Devices) - Reinstall drivers. Please wait until the installation process has ended.
6.Create the necessary virtual ports.
7.Save the settings.
8.Wait until the drivers for the new virtual ports are installed.
How to Use the Registry Editor
1.Type "regedit" (w/o quotes) in the Start menu search box
2.Right-click on the found Registry Editor application and select Run as Administrator.
3.Go to the branch HKLM\Software\Policies\Microsoft\Windows\DeviceInstall\Restrictions.
4.Set the value DenyRemovableDevices (REG_DWORD) to 0 (disabled).
5.Set the value DenyUnspecified (REG_DWORD) to 0 (disabled).
6.Restart your computer to apply the changes.
7.In the program Virtual Null Modem, select System (Devices) - Reinstall drivers. Please wait until the installation process has ended.
8.Create the necessary virtual ports.
9.Save the settings.
10.Wait until the drivers for the new virtual ports are installed.
Upon completion of virtual port installation, you may configure the initial values of the policy settings.
Make sure that driver installation from Windows Update is enabled.
1.Control Panel - System and Security - Advanced System Settings - Hardware - Device Installation Settings.
2.Select "Yes (recommended)".
3.Click OK and save the changes.
If the steps above do not help, the Windows may be corrupted. Then it is recommended to check the system files:
1.Type "cmd" (w/o quotes) in the Start menu search box.
2.Right-click on the Command Prompt application and select Run as Administrator.
3.In the command prompt, type "sfc /scannow" and press Enter.
4.The utility will check the Operating System for system file corruption.
5.Please wait until the system file check is complete.
Failure to install the driver may be due to a corrupted database of the device.
1.Follow steps 1 and 2 from solution 5.
2.To run the check, type in the command line: Dism /Online /Cleanup-Image /ScanHealth
3.To fix errors, type in the following: Dism /Online /Cleanup-Image /RestoreHealth