Half way through the single player campaign, I decided to try online play with a friend. After a few missions together, I alt-tabbed to check a message on skype.
In typical ubisoft fashion, I was unable to get back into my game or use my desktop and had to resort to ctrl+alt+del and kill blacklist there.
Since then, as soon as I run blacklist I get the error "Blacklist_game.exe has stopped working".
I have validated my game files on steam, tweaked the video settings ini and removed it altogether so it can be regenerated.
I opened a support ticket but I don't expect a reply for another few weeks, so any suggestions from you guys?