howto-remotely-disconnect-a-terminal-services-session

Authenticate to the server you wish to manage. You can
easily accomplish this by mapping a network drive to a share on the
target server. Start a command prompt and type

/qwinsta /server:yourservername/

where /yourservername/ is the name or IP address of the server you wish
to manage.

In my case I ran /qwinsta /server:10.0.0.2/

<http://thebackroomtech.files.wordpress.com/2008/04/qwinsta1.jpg>

You can see the Administrator account is logged into session 0 and the
admin account is logged into session 1. To disconnect the admin session
with ID=1 I'll run the following from a command prompt:

/rwinsta ID /server:yourservername/

where /ID/ is the process ID of the sesstion you wish to terminate, and
/yourservername/ is the name or IP address of the server you wish to manage.

In my case I ran /rwinsta 1 /server:10.0.0.2/

<http://thebackroomtech.files.wordpress.com/2008/04/rwinsta.jpg>

I again ran /qwinsta /server:10.0.0.2 /which verified session 1 had been
disconnected. I confirmed that I was once again able to login to
Terminal Services.