Restrict user to a single RD session
Under Windows Server 2012 & 2012 R2, there is no specific setting under RDP-TCP as it is not available.
- Restrict User to Single session:
To restrict the user to single session (Disable Multiple RDP Session) you can configure the setting under group policy (Figure 4).
Computer Configuration\ Administrative Templates\ Windows Components\ Remote Desktop Services\ Remote Desktop Session Host\ Connections
Restrict Remote Desktop Services users to a single Remote Desktop Services session Enabled