why the game don't start
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emaxxli post a screenshot of your game folder and one of the game settings in the launcher.
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sorry but it is in Italian -
Dss0 ok
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MW3 - https://plutonium.pw/docs/install/#iw5-modern-warfare-3
BO2 - https://plutonium.pw/docs/install/#t6-black-ops-2You don't have the basegame files.
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"Desktop" is not a folder that contains your Modern Warfare 3 files like the guide explains.
Take your time to read the install guide. If you have no idea what to do then just do exactly as it says.
You download MW3 and tell the launcher where MW3 is, not your desktop or another folder, MW3