Managing Remote Desktop Services (RDS) Client Access Licenses (CALs) through the Windows Registry is often necessary for troubleshooting licensing errors or configuring servers in environments where Group Policy is not applied. Key RDS Licensing Registry Keys
Before modifying any licensing keys, it is standard practice to export the registry subkey
"Look here," she pointed to the LicensingMode key. "It’s set to 5. That’s the ghost code. It doesn't know if it wants Per User or Per Device." rds cal license registry key
The main registry key for RDS licensing is located under the HKLM (HKEY_LOCAL_MACHINE) hive. The specific path has changed slightly across different Windows Server versions, but for modern releases (Server 2012 R2, 2016, 2019, 2022, and 2025), the primary location is:
If Group Policy is not applying correctly, manually changing the LicensingMode That’s the ghost code
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HKLM\SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services LicenseServers LicensingMode Microsoft Learn 2. The RDS Grace Period (The "Timebomb") rds cal license registry key
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod Target Entry : A binary entry starting with L$RTMTIMEBOMB Steps to Reset Take Ownership : Right-click the GracePeriod folder, select Permissions , and change the to the local "Administrators" group. Grant Permissions Full Control to the "Administrators" group. Delete Key : Right-click the
Windows Server provides a 120-day grace period before it strictly requires CALs. This state is tracked by a specific binary registry entry often called the "timebomb".