Infinite ammo in Halo 3?

[Brad]

Before I start a custom game I go to options and enable infinite ammo, but when the game starts, I don't have infinite ammo. Why?

 

[armoman92]

this is a common problem with halo 3 (i had it a while ago), its caused by a saving error. The only way i've heard you can fix it is by formatting your hardrive.

 

[harrylive92]

The ammo chip in your xbox is broke, i advise calling your nearest xbox shop and getting it replaced.