One workaround would be to use Win9x, which doesn't care if you overwrite random memory ;) I'd rather print a binary dump of the code and step through it on paper :D. Seriously though, I don't think it's our code that throws these errors (although VDub's use of catch(...) is what catches it) -- it's in the runtime. I was referring to when Avisynth displays the red-on-black "Unhandled exception" messages. Surely that's Avisynth and not the runtime?