I have an ESXi server that runs a Win-7 virtual server on it.
I use the Win 7 OS to run VSphere client so I can access the ESXi server and tweak it if necessary (this is the cheap homebrew solution)
I run Cygwin on the win-7 machine and I use ssh to pull ports so I can attach to the server using Remote Desktop using a secure connection.
Well today I ran into an issue. When I tried to log in I was met with this screen.
"The number of connections to this computer is limited and all connections are in use right now"
I still had Cygwin command line access to the machine so I looked around to see what I could do.
I found this post http://www.edugeek.net/forums/windows/31991-killing-remote-desktop-sessions.html  wjere iser e-class suggested using the following command line commands from Cygwin (though they are really DOS commands)
This did list the connection as still open, it also showed the ID
He also suggested using the following command to kill the session
> logoff 2
(in my case the session id was 2 so I used 2 you may have another session ID)
And when I ran this it seemed to work, at least re-running the quser command did not bring anything up. But when I tried to log back in I got the same results.
So I found this post http://stackoverflow.com/questions/5104523/how-to-execute-shutdown-command-from-cygwin-in-windows  where a user Frankie suggested using the DOS shutdown command to reboot the server
I ran the command
> shutdown /r /t 0
The server successfully rebooted and I was able to get in and open a Remote Desktop session.
 Windows Thread, killing remote desktop sessions? in Technical; hi all, anyone any ideas as to how I can kill dead remote desktop sesisons?
 How to execute shutdown command from cygwin in windows