Windows never fails to throw odd ones at me. Recently, while repairing a severe spyware infection I ran into the error: Error Starting Program – A required .dll file, MSASN1.DLL not found, when running both AdAware and Spybot: Search and Destroy. It would happen when attempting to load other programs as well.
The fix was simple enough, though. In this machines case I just copied the msasn1.dll file to the Windows directory as well as the WindowsSystem directory. Now, you can attempt to run your programs at this point. If it gives you the same error still, fret not. The .dll has just been unregistered, and it’s easy enough to remedy that. Simply click Start->Run and type regsvr32 msasn1.dll. This will add the .dll file to the registry so Windows knows it’s there and can use it. You should now be good to go!