I was also seeing this: Errno architecture (MSWin32-x86-multi-thread-4.0) does not match executable architecture (MSWin32-x86-multi-thread-5.0) at C:/Perl/site/lib/Errno.pm line 11. I first tried to upgrade any possible modules with ppm. Then - I uninstalled ActiveState Perl and downloaded their latest release - reinstalled some modules I use and ran the program again and it worked. Thanks - Mark