pvxwin32.exe stopped interacting with windows

Hello,

We have been having an issue with Sage 100 Advanced 5.0.7 where the launcher freezes. open modules continue to work but no other modules can be opened and the launcher cannot be closed. The Launcher becomes completely unresponsive. 

We have serverl users accessing Sage directlyon the LAN and several more through a pair of Citrix servers. The problem seems to begin with the LAN users, but then can spread to the Citrix users. The folowwing error occurs on the Application server.

The program pvxwin32.exe version 9.40.5.0 stopped interacting with Windows and was closed. To see if more information about the problem is available, check the problem history in the Action Center control panel.
Process ID: 47f8
Start Time: 01d00f3e8e0d8423
Termination Time: 15
Application Path: C:\Accounting\Sage_100_v2013\MAS90\Home\pvxwin32.exe
Report Id: 7eb9f6e2-7b32-11e4-a434-00155d537017

Any thought?

Thanks

TJ