If you are looking to download a save game (for example, to have all cars unlocked) on an Xbox 360, you cannot simply copy it to a USB drive and play. The Xbox 360 has a security measure that ties saves to the specific console and profile ID.
If you copy another user’s Forza Horizon 1 save file to your console without resigning it, the game will detect a signature mismatch. Result: message or the game simply ignores the file. forza horizon 1 save game exclusive
