I had this problem, and came here looking for my solution to it. I never "fixed" the bug, but I found a work-around. Renate the extenstion to .EXE (in uppercase) and it works like a charm.
-- Mimetype error: *.exe => the filename indicates "executable", while the contents indicated "DOS/Windows executable" https://launchpad.net/bugs/91636 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
