I like a guy not faint of heart...disable anti-virus proggie and scan for Windows updates. Install 811943 and reboot on prompt. If it starts up and runs, fine...if not, disable anti-virus and uninstall thru control panel/add/remove programs and reboot on prompt. One or both of these should work...if I hear gunfire I'll know it didn't. What ever you do don't give up we're on the right track.