Windows Server: How to Reset the Remote Desktop Services Licensing Grace Period

The Remote Desktop Services (RDS) role in Windows server requires appropriate client access licenses (CALs) to be installed in order to function properly. However, there is a 120-day licensing grace period which begins when the role is installed. During this grace period, RDS functions without any CALs having been installed. This is to allow an organization to configure and test its RDS environment to ensure that everything works as expected before purchasing and installing CALs.

It is possible to reset this grace period, but resetting the grace period is not a substitute for purchasing and installing the required Remote Desktop CALs. The following steps should not be performed on a server that is in production.

To reset the RDS licensing grace period, perform the following steps:

1. On the RDS session host, launch Registry Editor (regedit) as an administrator.
2. In regedit, browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod.
3. Within this registry key is a REG_BINARY entry whose name begins with the string L$RTMTIMEBOMB. (This is likely the only entry in this key.) The default permissions on this entry do not allow it to be modified or deleted, so these permissions must be changed.
4. Right-click the GracePeriod folder in the left pane of regedit and select Permissions.
5. In the permissions window that appears, select Administrators, and assign this group Full Control permissions. Click OK to close the window.
6. If an error indicates that the permissions could not be changed, take ownership of the folder by following these steps:
   1. If the permissions window is no longer open, right-click the GracePeriod folder and select Permissions again.
   2. Click Advanced.
   3. At the top of the Advanced Security Settings window, Click the Change link next to the current owner.
   4. Type Administrators in the blank and click Check Names. Confirm that the local Administrators group is listed and click OK.
   5. Check the box labeled Replace owner on subcontainers and objects and click OK.
   6. Click OK again to close the permissions window, then attempt to change the permissions of the folder again.
7. Right-click the L$RTMTIMEBOMB... registry entry and select Delete. Click Yes to confirm the deletion.
8. Exit regedit.
9. Reboot the session host server in order for the registry change to take effect.

You may confirm that the procedure was successful by using the RD Licensing Diagnoser tool from the Tools menu of Server Manager. Clients should now be able to connect to this session host without the applicable CALs. Again, this procedure is not intended to be a substitute for purchasing and installing Remote Desktop CALs. It should only be performed in a non-production (that is, a test or lab) environment.

(invoke-cimmethod -inputobject (get-ciminstance -namespace root/CIMV2/TerminalServices -classname Win32_TerminalServiceSetting) -methodname GetGracePeriodDays).DaysLeft