Click the NEW THREAD button (lower left corner) to start a new topic. I have moved the post for you.
The problem you are having is not PDMS related (first clue, it works for 20 users, second clue, after rebuilding the machine it worked for a few days), but maybe workstation/network related to your IT environment.
So check with your IT, ask them what have changed recently, what logon scripts they are running and what reg-key they may have changed etc etc...
