I've played 1,291 hours in Call of Duty Modern Warfare 3 to date. When I try to play now I get the above error message. I've already tried verifying the integrity of the game cache through steam which says it's fine. When I go into the game file folder tho, there is only the .exe file for single player(iw5sp), the iw5mp file is gone. Has anyone experienced this issue? Single player works fine but no multiplayer through steam, desktop shortcut or by going to main menu in game and then selecting multiplayer. Would appreciate any feedback or suggestions, google didn't help.