Obvious question first.. Are you on DEX firmware? (Or have you set up ControlConsoleAPI correctly?)
Secondly, are you sure you're using the correct EBOOT version? (i.e, if you use a 1.19 mw3 eboot on the 1.24 patch, the game will not load up/crash.)
If you need any extra help, add me on skype: [email]
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