After a reboot, the grace period restarts — but this is , and Microsoft does not support it for production.
Step-by-Step Technical Overview of Resetting the Evaluation Timer
Ensure your RD Session Host is explicitly configured to communicate with your license server. This can be defined via Group Policy Object (GPO) to prevent the system from falling back onto grace period errors:
In legitimate test and development environments, administrators often need to reset this timer. The configuration for this grace period is stored securely within the Windows Registry. The Grace Period Registry Path: rds cal license registry key free
) to Activate Server and Install Licenses using a valid agreement number.
Windows Server allows two concurrent administrative remote connections (often called the "Admin mode"). Once a third user tries to connect, the server demands a Remote Desktop Services Client Access License (RDS CAL).
For the changes to take effect, restart the Remote Desktop Services service via services.msc , or completely reboot the server. Upon reboot, a new 120-day counter will begin. Rebuilding a Corrupt RDS CAL Registry Instance After a reboot, the grace period restarts —
1. Activating a Free Trial via Microsoft Evaluation Programs
In test environments, administrators frequently reference a specific registry key responsible for tracking the grace period countdown. This key dictates how much time remains before enforcement begins.
reg delete "HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod" /f The configuration for this grace period is stored
The Windows Registry stores configuration data for the Remote Desktop Licensing service. When a user connects to a server, the server checks the to see if a valid CAL is available.
In isolated sandbox or development environments, systems engineers often back up and delete the binary value contained inside the GracePeriod key. After a system reboot, the Remote Desktop Services stack detects the absence of the tracking key, generates a new one, and resets the evaluation counter back to 120 days.
: These are required for each user or device that accesses a Remote Desktop Session Host (RD Session Host) server. There are two types of CALs: Per Device and Per User. The Per Device CAL is assigned to a device, and the Per User CAL is assigned to a user.
Understanding RDS CAL Registry Keys: Architecture, Mechanics, and Licensing Compliance
Simply enable Remote Desktop in the System Settings. Do not install the "Remote Desktop Session Host" role. Microsoft Evaluation Licensing