I have 4 Windows 7 Pro workstations running Medisoft 16. They connect to the Windows 2008 x64 server through Advantage Database server. If I try to open Medisoft on one of the workstations, I get an Error 6420. If I close out and try to open again, it goes right in. If I close Medisoft again and open it back up, it still goes right back in. If I go to another workstation, I get the same Error 6420. Again, when I close out and open back up, it goes right in. If I go back to the first workstation, I get the Error 6420 again. Any ideas as to what the problem is here? I'm really baffled and not really sure how to diagnose this problem.