Halo reach maps on cea

When I loaded the game it asked me if I wanted to redeem the halo reach maps to cea. The problem is I don’t know what the code is or where to find it. If any one knew where this code to redeem the maps may be that would be very helpful.

Well, you can play the anniversary maps off the anniversary disk without the code. Though you only have those 7 maps. The code is so you can play the maps on Halo: Reach. If you bought it new, there should be a code on the side with the game manual to download the maps.