See if the pvxwin32.exe is running using task manager. Try running as administrator.  Firewall and/or anti-virus settings may be stopping it.

If this is still an issue, try renaming the Sage 100 folder in the c:\Users\"user name"\documents folder.  Then launch Sage .

If you see the Sage program on the Start bar, but not the login prompt, try: Alt+space, M, arrow keys.  This helps when the login prompt is off the screen, and will snap the hidden window into visible space.

Thank you for all your help.  I determined that our antivirus was locking some .vbs files during the Workstation Synchronization process.  After adding those files as exceptions, everything worked as expected.