On chapters 11 and 14 optional co-op only missions(disc 2),I am able to complete the entire mission but on the elevator ride right where it would say complete and saving it locks up and I have to restart my xbox before I can do anything.... I have tried all of the tips and solutions for these types of problems I could find with no luck.(deleting cache and updates,uninstalling the game) Any other ideas out there? I would think the disc is bad but I have played the entire game from start to finsh twice now on single player with not one other problem. no scratches or any visible damage.
ps. and i have no problem connecting to games or people joining and playing the campaign its just at the end of the co-op only mission after we've played thru the mission right before the save