Also, in SOS 4.0, this error message appears in the log file:
These error messages indicates that a copy of the Visual SourceSafe Client has not been installed on the SOS Server machine. The VSS client provides the API that the SOS Server needs to communicate with the VSS database.5/4/04 9:58:56 AM - 2: Exception during Login: COM object with CLSID {783CD4E4-9D54-11CF-B8EE-00608CC9A71F} is either not valid or not registered.
5/4/04 9:58:56 AM - 2: COM object with CLSID {783CD4E4-9D54-11CF-B8EE-00608CC9A71F} is either not valid or not registered.
If the VSS Client is on the SOS Server machine, you may need to register the automation component using the steps in this KB article:
http://support.sourcegear.com/viewtopic.php?t=255