So As you can see I have the FOTUS armor on this site, unfortunately when I finally got the new Halo 4 copy I ordered to work…I could no longer use the armor in the game. Probably having something to do with me trying to get the Halo 4 Disk 1 to work yesterday and deleting the game as well as the Xbox360 Cache and I was wondering if there was any way to retrieve these items…if I had done so?
download history
redownload
???
> profit
You can go to your download history and re download it see if that works. All my DLC items seem to vanish every once in awhile and thats what I do to get them back. 
Well, if you accidentally deleted the armor, you know that you can download it again via xbox.com in the recent purchases. Regarding disks…I really dont know.
Thank you good sir.