Limit a Windows 7 machine to 1 user login at a time

Question

I've searched everywhere for a solution to this but have not found anything outside of restarting the machine.
I need to limit a Windows 7 computer to only allow one user logged in at a time. This machine has applications only allow one user to run them at a time. So if a user locks this machine and walks off and if the next user switches user and logs in, none of
the programs will work because the first user's session is now suspended.
Is there anything that will kick the suspended user off? So if a user forgets to log out and the screen is locked, the second user's login would force the first user to log off?

Answer 1

I know this was 1.5 year ago, but people search the web for these solutions for years and for years these solutions continue to help others, but not when people are so very much OFF TRACK with what the OP asked for. It shouldn't surprise me, but it is astounding
at how people do not communicate well and instead of reading what the OP asked for carefully the proposed answer here does NOT address the OP's question... it got the "BREEZE BY ANSWER".
NOW - TO the OP Cherickson HERE's the BEST answer I've been able to determine on my OWN since ALLLLLLLLL of the other posts online I read ALSO were answered OFF TOPIC:
DISABLE FAST USER SWITCHING (speaking from a Windows 7 environment)
Here's the GPO to do it (Open Group Policy Management Editor on a DOMAIN or Active Directory server):
Default Domain Policy [ServerNameHere] > Computer Configuration > Administrative Templates > System > Logon > Hide entry points for Fast User Switching
Set Hide entry points for Fast User Switching to Enabled.
FOR non-DOMAIN non-Group-Policy controlled PC's use "Local Group Policy Editor" via gpedit.msc
(NOT NOT NOT "Local Security Policy" via secpol.msc) and visit:
Local Computer Policy > Computer Configuration > Administrative Templates > System > Logon > Hide entry points for Fast User Switching
Set Hide entry points for Fast User Switching to Enabled.
Now, to be "EXACTING" here, this does not "PREVENT" multiple users from logging into the same PC at one time "per say", but it ends up having that effect on "PEOPLE" because "PEOPLE" are very predictable
in a network environment and they aren't worried about saving PC resources for themselves or others... they just use the PC.
Setting Hide entry points for Fast User Switching to Enabled REMOVES the option for users to "SWITCH USER" while they are logged into Windows (fat client) and it also removes the "SWITCH USER" from the Welcome/Logon screen,
thereby forcing them to "LOG OFF" themselves (or whomever is logged in) manually and thereby then they are presented with an option to Log In using their own Windows user account. This is great, because it keeps the PC resources for just 1 logged
in user at a time instead of you being called to examine a slow PC only to find that the lazy users out there left 2 or 3 or MORE users logged in at once despite being told 100 times or more that they shouldn't do that. :) EXPERIENCE??? :)
Now, if you have an advanced user, doing things with other users logging in the background of their own user session (IE: RUN-AS on some shortcut lets say) then they should still be able to do all that jazz too even though Fast User Switching is turned off.....
but this is usually pretty unlikely and usually that would be someone amongst the IT staff.
So to summarize:
Set policy "Hide entry points for Fast User Switching" to Enabled in order to have only 1 user logged on any given PC "at one time" - IE: Prevent concurrent Windows user Logins
NOW.... I elect MYSELF and MY ANSWER as BEST ANSWER in this THREAD, because its the ONLY ANSWER that addresses the OP's request.