Things You'll Need
Instructions
Press the guide button located in the center of the Xbox 360 controller. Select the "Recover Gamertag" option. Enter the email address and password associated with the Gamertag. When downloaded, sign into your recovered Gamertag.
Find the maps you want to transfer. Go to the "Game Marketplace" section on the Xbox 360 main menu. Select Game Add-ons. Choose to sort all title alphabetically. Select "C" for Call of Duty 4.
Select "Call of Duty 4" to see the list of all available downloadable maps. Any maps purchased under the recovered Gamertag will say "Download Again," whereas any unpurchased maps will have a price listed. Select the maps you want to download. If previously purchased, there will be no additional charge.
Insert the Call of Duty 4 disc into the Xbox 360. Any downloaded maps should now be accessible.