The ISO is corrupted, badly ripped, or intentionally modified. Do not use it. Safe Practices for Game Preservation
This comprehensive guide explains what verified ISOs are, why they matter, how to verify them yourself, and the current landscape of Xbox 360 preservation. What is an Xbox 360 ISO? games xbox 360 iso verified
Find the correct hash from Redump.org. Search for "Halo 3" and copy the SHA-1 value (e.g., 1A2B3C4D5E6F... ). The ISO is corrupted, badly ripped, or intentionally