Just overcome an extremely challenging problem we've been having. Our COM application was calling out to a dot net assembly through COM Interop and when the dot net assembly returned a response the process would get terminated... no friendly output, error messages, or log entries - just dead.
The solution was to totally REMOVE the Dot Net 2.0 framework and re-install. We tried a REPAIR first but that didn't seem to do anything.
It's worth mentioning that the problem didn't occur when calling into the dot net assembly but rather when it returned something to VB6... very strange.
Anyway, strike another issue off the project wall. Time to move back on to Prospecting!
Addendum> Apparently this issue is caused by one of the Dot Net 2.0 Security Updates from Windows Update! For now we're avoiding this patch.