Before touching the registry, you must understand where Windows stores its RDS licensing information.
: Open the RD Licensing Diagnoser tool on the Session Host to verify that the licensing mode and server list match your registry entries.
On the RD Session Host side, the operating system tracks how it discovers the licensing server and what mode it operates under. These settings are governed by specific registry keys, which are often mirrored or enforced via Group Policy Objects (GPOs). The TermService Parameters
Some RDS registry keys are owned by NT SERVICE\TermService . To edit them, you must: rds cal license registry key
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TermService\Parameters\LicenseServers\SpecifiedLicenseServers Policy-Based Settings : Configures licensing via GPO.
For large deployments, leverage PowerShell to manage registry settings programmatically. Here are useful commands:
This is the most critical location for troubleshooting "The remote session was disconnected because there are no Remote Desktop client access licenses available" errors. Before touching the registry, you must understand where
"Look here," she pointed to the key. "It’s set to 5 . That’s the ghost code. It doesn't know if it wants Per User or Per Device."
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSLicensing
: Useful in environments where you want to prevent a client from automatically upgrading to a higher version CAL. These settings are governed by specific registry keys,
The main registry key for RDS licensing is located under the 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:
For ongoing management, rely on proper license server deployment, Group Policy, and regular event log monitoring. Registry hacking should remain the last arrow in your quiver, not the first.
Follow these steps to reset the grace period: