Nvidia card? Force Anti-aliasing to be set to x2 before loading the campaign. Should (hopefully) fix the crash issue. If you have a more recent Nvidia card 6xxx or 7xxxx series, I wouldn't roll back the drivers because the drivers that work with MTW won't be optimised for your card, possibly as your card wasn't even out then.

This is the third time I've replied to this crash issue in the space of about 10 days. Might as well have a big blinking sticky topic saying, 'Game crashes when loading Campaign map? CLICK HERE!!!' if there isn't one already, as people apparently can't find the threads for themselves.