How to activate the Windows Remote Desktop Service (RDS) Role and configure the session host
When is the RDS role needed?
The default server setting is RDP Admin mode, which allows single sessions with the appropriate privileges. If there is only one user, then additional RDS (Remote Desktop Service) licenses are not required.
If multiple users need to connect to the server simultaneously, each user needs a Remote Desktop Server Client Access License (RDS CAL) added to the license manager, with the session host configured to use that license manager.
Note: If this is not done, the RDS will go into Evaluation Mode, which will expire after 120 days, effectively locking users out. An error message ‘Remote Desktop licensing mode is not configured‘ will be displayed.