I was surprised to find this on the Dell support site.
Instructions
It is possible to reset this grace period, but please note: resetting the licensing 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:
- On the RD session host, launch Registry Editor (regedit) as an administrator.
- In regedit, browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod.
- Within this registry key is a REG_BINARY entry whose name begins with the string L$RTMTIMEBOMB. (This is likely the only entry in this key.) The default permissions on this entry do not allow it to be modified or deleted; therefore, these permissions must be changed
- Right-click the GracePeriod folder in the left pane of regedit and select Permissions.
- In the permissions window that appears, select Administrators and assign this group Full Control permissions. Click OK to close the window.
- Right-click the L$RTMTIMEBOMB... registry entry and select Delete. Click Yes to confirm the deletion.
- Exit regedit.
- Reboot the RD session host server in order for the registry change to take effect.