kicking / logging out remote windows users?

Refer this post on kicking the users.

The summary of the commands is as follows:

Use qwinsta to get a list of the Remote Sessions in the command window (Get the session Id of user to kick out):

qwinsta /server:SERVERIP

Use rwinsta to disconnect the remote session:

rwinsta /server:SERVERIP SESSIONID

Also you may want to change the default timeout for idle RDP connections.here or here.

You should also be able to do this by pulling up Task Manager and going to Users and selecting users to Logoff or Disconnect. Disconnect will close their RDP session, but they can log back in to it. Logoff will... well, log off their current session.