Rather than manually editing the registry on each RDSH server, use Group Policy to enforce licensing settings across all domain-joined session hosts. This reduces configuration drift and simplifies management.
By default, even Administrators cannot delete this key due to restricted permissions.
The Windows registry holds several essential keys that control RDS licensing behavior. Understanding these locations is the first step toward mastering RDS license management.
Understanding the specific registry paths, keys, and values associated with RDS CALs is critical for system administrators tasked with troubleshooting activation issues, backing up licensing databases, or resetting grace periods. The Primary RDS CAL Registry Paths
When you first install the RDS role, Windows grants a free 120-day licensing grace period. This period allows an organization to test the RDS environment without having to immediately purchase licenses. This grace period is tracked by a value inside this key, which usually begins with the string L$RTMTIMEBOMB . The default permissions on this key are designed to prevent modification, and changing it requires taking ownership of the folder. rds cal license registry key
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services
When a client device connects to an RDS host in Per-Device mode, the local machine stores its issued token locally. On the client computer, this is found at: HKLM\Software\Microsoft\MSLicensing\HardwareID and HKLM\Software\Microsoft\MSLicensing\Store Common Administrative Workflows Involving the Registry Resetting the RDS Grace Period
To reset this, an administrator must delete the GracePeriod key. However, Windows protects this key with specific permissions.
"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." Rather than manually editing the registry on each
The path is:
(invoke-cimmethod -inputobject (get-ciminstance -namespace root/CIMV2/TerminalServices -classname Win32_TerminalServiceSetting) -methodname GetGracePeriodDays).DaysLeft
On the RD Session Host or the RD Licensing Server, primary configurations and operational database paths are located here:
Sometimes, the RD Session Host ignores a perfectly healthy licensing server and thinks the grace period is expired. This is often due to a corrupted "timebomb" registry state on the local host itself. Resetting the grace period via the steps in Section 3 usually resolves this issue. The Windows registry holds several essential keys that
The registry keys for Remote Desktop Services (RDS) Client Access Licenses (CALs)
Understanding the RDS CAL License Registry Key: A Complete Technical Guide
Click , change the Owner to your administrator account, check the box for "Replace owner on subcontainers and objects", and click Apply .
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.