If this doesn't work try starting over, there's a chance your game is newer and patched to fix the exploit hole. The save game should start to load, after a wait of about 10 seconds it should load the UnleashX dash. Make sure it loads from the hard-drive and if needed delete any existing save games that you may have had before you copy the game save exploit over.
Time to Load our save game: Start the 'Mechassault' Game, once in the game and it's loaded select the option to load a saved game.
If you actually have a 'Live' account you probably don't need to do anything as your Dashboard will be up to date. You can do this simply by choosing the 'Live' options and select 'Account recovery' this updates your dashboard automatically and once finished will ask you for details of your account to continue, just quit as you've accomplished the task of updating the Dashboard. Prepare your Xbox: First thing you should do If possible is to connect your Xbox to the Internet and update your Dashboard. Video Get the save game on your Memory Card Use an Action Replay or GameShark to get the save on your Xbox There are two ways you can install it: watch the video or read below if the video doesn't make sense.