If you are managing the itself:

If you set SpecifiedLicenseServers but GPO settings push a different value, your manual edit will be overwritten on every Group Policy refresh (every 90–120 minutes). Check: Computer Configuration\Policies\Administrative Templates\Windows Components\Remote Desktop Services\Remote Desktop Session Host\Licensing

Remote Desktop Services (RDS) relies heavily on the Windows Registry to manage Client Access Licenses (CALs). When a user or device connects to an RD Session Host, the server checks for a valid CAL. If licensing issues occur, or if you need to reset a grace period, clear a stuck temporary license, or change your licensing mode, you must modify specific registry keys.

By respecting both the technical safeguards (like backing up the registry) and legal boundaries (staying within compliance), you can turn the Windows Registry from a black box into a precise instrument for keeping your Remote Desktop environment alive and lawful.

and select Manage Licenses .

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\Licensing Core Specified License Server : Defines the server(s) issuing CALs.

Store : Contains the actual digital licenses ( LICENSE000 , LICENSE001 , etc.) issued by the licensing server. 2. Server-Side Licensing Database Registry Key

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

Warning: Modifying the Windows Registry incorrectly can cause severe system instability. Always back up your registry keys before making changes. The MSLicensing Key (Client-Side)

and restarting the Remote Desktop Licensing service forces the system to regenerate them. Forcing Licensing Mode:

When a device connects to an RD Session Host, the host issues a hardware-bound token or digital license. The client machine caches this license locally in the following registry path: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSLicensing Use code with caution.

Interfacing with the RDS CAL registry keys is a powerful troubleshooting technique, but it should be treated as a targeted fix rather than a permanent licensing management strategy.

: If you change LicensingMode or SpecifiedLicenseServers in the registry and find they revert after a reboot, a Group Policy Object (GPO) is enforcing those values. Update the policy via gpedit.msc or your Active Directory domain controller instead.

When a client (workstation) connects to an RDS server, it receives a temporary CAL token stored locally in the registry. This token is typically valid for 90 days. If a full CAL is available, the temporary token is upgraded to a permanent license stored in the same location.