I’ve just come across a terminal server that wouldn’t let me log on. Turns out the maximum number of users the terminal server is licensed for has been exceeded.

Thusly, from another machine on the network, we open a command prompt and type

qwinsta /server:<servername>

This will give a list of the terminal server sessions on that server, note the ID number (aka sessionid) as we use them in the following commands.

We can reset a session by using

rwinsta <sessionid> /server:<servername>

or we can disconnect the session with

tsdiscon <sessionid> /server:<servername>

or we can logoff a session with

logoff <sessionid> /server:<servername>

Dan Rigsby has more info as does Scott Forsyth.