Restrict multiple logons

I have a w2000 domain. 2 Domain controllers, 1 Citrix server, 1 exchange server, 1 file server. All running w2000 server. I want to restict users so they can only log on to the domain once at one station and must log off that station before they can log on somewhere else.

The purpose is: I have a folder that I only want 1 user at a time to be able to use so I will set up a “John Doe” account that is the only user that has rights to that folder. Then everyone can use that account but I want it to only be able to log on once so multiple people cannot log on with the same account simutaniously. OR is there a better way???

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