How to transfer my Halo Reach Flaming Helmet???!!!?

Those items are likely restricted to only working on the registered system, which since you redeemed the codes and downloaded them originally on your friend's system, would be his. There is a fix for this, though your friend will loose access to them. Use the once a year License Transfer tool to register the downloads to your system: a href="http://www.xbox.com/en-us/support/systemuse/xbox360/licensemigration/default.htm" rel="nofollow"http://www.xbox.com/en-us/support/system…/a