I order to prevent all your terminal service sessions being used and
thereby blocking access to a server,
tsadmin can be used to log users
off remotely or session timeouts / limits can be imposed.
Add the following Registry entries, creating a 1 hour disconnected session limit and a 2 hour idle session limit:
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Control\\Terminal Server\\WinStations\\RDP-Tcp] "MaxDisconnectionTime"=dword:0036ee80 "MaxIdleTime"=dword:006ddd00
To add the entries save as whatever.reg and double-click.