Policy
Do not allow COM port redirection
Microsoft Windows
Policy overview
Key metadata and intent for this policy.
Supported OS tags: Windows10, Windows10RT, Windows11, Windows7, Windows8, Windows81, WindowsRT, WindowsRT81, WindowsServer2003, WindowsServer2008, WindowsServer2012, WindowsServer2012R2, WindowsServer2016, WindowsVista, WindowsXP
This policy setting specifies whether to prevent the redirection of data to client COM ports from the remote computer in a Remote Desktop Services session. You can use this setting to prevent users from redirecting data to COM port peripherals or mapping local COM ports while they are logged on to a Remote Desktop Services session. By default, Remote Desktop Services allows this COM port redirection. If you enable this policy setting, users cannot redirect server data to the local COM port. If you disable this policy setting, Remote Desktop Services always allows COM port redirection. If you do not configure this policy setting, COM port redirection is not specified at the Group Policy level.
Registry values
How enabled and disabled states update the registry.
| Scope | Registry location | Type | Enabled value | Disabled value | Copy |
|---|---|---|---|---|---|
| Computer | Path SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services Value name fDisableCcm | REG_DWORD | HKLM 1 | HKLM 0 |
Policy elements
Inputs and configuration options exposed by this policy.
This policy has no additional user input fields.