Unexpected errors during startup can manifest as many different error messages. It can be a window telling the user that the add-on simply shut down or even that no error at all happen but the add-on doesn't start.
There are several possible causes for this problem (here listed as most likely):
- The windows user does not have correct permissions for running the add-on (see system requirements) or try to log in as an administrator to verify that the problem persist with this user
- The add-on installation is corrupt or is missing one or more files. Try reinstalling the add-on
- The add-on was installed on a shared drive. This is not possible due to a security design of the Microsoft .NET Framework. Reinstall the add-on of a local drive.
Also try looking for problem indicated in the Windows Event Viewer, The SAP Log or the B1 Usability Package log.