nothing, the only way to prevent complete information corruption is to save your profile in a USB device every 3lvs or so I learned it the hard way.
Bad disk
Reinstall the game.
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well call of duty and modern warfare are the same it is called Call of Duty: Modern warfare and then came call of duty: modern warfare 2
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you get unlimited ammo
Makarov does not take part in Modern Warfare 2, because he dies on Call of Duty 4: Modern Warfare. He gets shot by Sgt. Soap Mactavish the person you play as. I don't want to spoil what exactly happens. Soap is also on Modern Warfare 2.
Call of Duty 4: Modern Warfare came out first. This is the first game in the Modern Warfare series, and Modern Warfare 3 is the third game in the Modern Warfare series.
Call of Duty Modern Warfare came before Call of Duty Modern Warfare 2
no theres a call of duty modern of warefare 2
You either turned it off without exiting or the internet got an upgrade on that game
Call of Duty 4: Modern Warfare was just before Call of Duty: World At War, and Modern Warfare 2 came just after it. Unless its on the Wii, on the Wii its WaW the Modern Warfare but its called Modern Warfare Reflex