Start your XBox 360 without a disc inside so that you have access to the dashboard If you do not have this information please visit the XBox Live website or call them at 1-800-4MY-XBOX. The following will involve recovering your Gamertag, so make sure you know the Gamertag name, the email address, and password associated with the account. NOTE: The following involves deleting your Marvel Ultimate Alliance saves. If you do not have a Live Enabled account DO NOT DO THE FOLLOWING.

NOTE: The following requires that your account be an XBox Live enabled account. If you have already entered a cheat code and saved the game you can do the following the restore your ability to get achievements. Game altering codes will disable all achievements, using a cheat code to unlock a character will make it impossible to get the Achievement awarded for unlocking that character. This is due to security measurements determined by Microsoft in order to avoid exploiting the game to gain Achievements. If you have input a cheat code and saved the game, you will be locked out of being awarded any Achievements you have not already completed. Thanks for the website, I browsed it and found the following.

Marvel ultimate alliance 1 cheats