I know that you can disable fast user switching through GP but what I would rather have is the ability for a new user to log on and have whomever is currently logged on/locked forced to log off. This behavior exists with remote desktop, that if you are trying to RDP to a machine that someone else is already logged in to it will warn you at the log on screen and ask if you want to proceed.
I know I'm going to get asked why... well because we have some POS software that will not work if more that one user is logged on to the machine and we also have a security policy that forces the machine to lock after 20min. So someone logs in does what they need, walks away and then no one else can run that software until the other person logs off. Also no one is an admin on this machine so they can't log off another user through the task manager.
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