sqlserver.exe error

[BJCameron]

I have developed a distributed application which uses SQL Server Express 2005. The program installs and runs successfully and is in use by a number of people - it is a single user app.
There have been a couple of clients now who have started to get the following error message when they run the program, having previously had no problems with it:

sqlserver.exe has stopped working. A problem caused the program to stop working correctly ...

The only common factor is that in the SQL Server Configuration Manager>SQL Server 2005 Services they have MSSMLBIZ running. Is this a known conflict? There are no problems when the only services running are SQL Server (SQLEXPRESS) andSQL Server Browser.

Any ideas please? I need to get the program running again for these clients.