I beat the campaign on Normal back when Black Ops first came out. Sometime after that i lost my campaign progress so i used the computer code because i wanted to play the boat mission again. Now i want to try to re beat the campaign on veteran, but i have no idea how to re lock the missions or restore my single player progress. I've tried deleting my black ops info on my hard drive, but no luck. Does anyone know how i can restore my single player progress and get these achievements?