It is possible to take control of Session 0 from another user.

A user who is currently connected to Session 0 cannot prevent a session takeover. Furthermore, Windows provides no advance warning prior to a session takeover.

To steal control of Session 0, simply click the Steal From menu item. 

The RDP user is listed along with the client machine name. It is also possible to kick a user off Session 0 and leave it unoccupied.

This function is useful for cleaning up orphaned Session 0 connections, e.g. when a user connects to a remote server through RDP, switches to Session 0, and then disconnects the RDP session, thus leaving Session 0 inadvertently occupied.

For information about command-line parameters that are used to take control of Session 0, see Command Line Parameters.