Years ago, a friend came over and let me borrow his Oblivion GOTY edition. I downloaded the DLC and played a bit. After he left with the game, the DLC was still on my Xbox 360 and I have had it ever since. After picking it up for myself, I noticed it gave the option to buy the DLC from the market place, so it doesn't register that i have the DLC. Does that mean that it doesn't update the DLC files? Will I have to buy the DLC from the marketplace just to have it up to date?