Key: Rds Cal License Registry

For Macintosh RDP clients, licenses are stored as files on the local computer in the folder hierarchy under:

If you delete the MSLicensing key on a Windows Vista or later client and subsequent connection attempts fail with "An Error occurred in the Licensing Protocol," restart the Remote Desktop Connection as an administrator. This ensures the client has permissions to rewrite the necessary registry keys.

The licensing process involves a coordinated exchange between client and server using these registry keys: rds cal license registry key

If a receives a "licensing protocol" error, deleting the local license cache often forces a fresh request. Guidance for troubleshooting RDS Licensing - Windows Server

This guide details the critical registry keys responsible for RDS CAL storage, management, and troubleshooting on both Session Hosts and client machines. 1. The Client-Side RDS CAL Registry Key For Macintosh RDP clients, licenses are stored as

Located at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\Licensing Core , the LicensingMode DWORD sets the mode (2 for Device, 4 for User). License servers are specified under HKLM\SYSTEM\CurrentControlSet\Services\TermService\Parameters\LicenseServers . 2. Group Policy and Troubleshooting License Remote Desktop session hosts | Microsoft Learn

Running the client as an administrator on the first subsequent connection is mandatory. It grants the Remote Desktop client the necessary permissions to recreate the deleted registry keys and successfully request a fresh, valid token from the license server. 2. Terminal Server Client Settings (Host-Side) Guidance for troubleshooting RDS Licensing - Windows Server

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".

Within the Licensing Core key, look for a DWORD value named . You can alter this value to switch between the two primary RDS CAL models:

reg delete "HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod" /f