I had a similar problem last night. I found out what the problem was: That little scratch-off card they provide (which contains the free Madden code) actually has two codes on it. I started scratching the card from the bottom-up and stopped as soon as I saw the first 25 character code. Well, that's the wrong code. That code is actually for something else (like an add-on for the actual game). Scratch off the entire card and you will see that the code you actually need for the Madden game is at the top. I realized this mistake after I chatted with Microsoft and they told me that I was using the wrong code.