>I know...VFP6 (long story). I have created a multi-threaded DLL to be called from Biztalk's 2002 Orchestration Designer (XLANG). The DLL is registered on the Biztalk server, but when I try to call it, I'm getting the "Class not registered" error in the BTS event log. Is the problem that the interface in VFP6 is not compliant with what BTS needs?

Christopher,
How have you verified that the class is registered properly? Can you instantiate the class on that box using another tool (e.g. VB, VFP, VBA in Office, etc.)?