Infinity Ward - If you are having trouble after downloading the latest Call of Duty: MW3 DLC Content Collection 4 pack for Xbox 360 here is a workaround to launch the game
Guide to MW3 in 2021 : r/mw3
Call Of Duty: Modern Warfare 3 (MW3) Cheats, Codes, Cheat Codes, Perks, Walkthrough, Guide, FAQ, Unlockables for Xbox 360