I have installed Fallout 3 and have been playing for the past month... Great game. But whenever I tried to login to Live, it tells me that my Product Key is Invalid and therefore I can't login. I've been playing other Live games so I don't think that's the issue... it's just that they don't recognize the product key that came inside the DVD case (which I bought from amazon.com). This hasn't affected my regular play, except that I don't get any achievments.

Second issue: I just installed disc 2 (the DLC) and the game does not recognize it. It took about a minute ot two to instal, but in the main Fallout 3 menu the "Download" button cannot be clicked. I even put disc 1 back in and highlighted all the "Data Files" (box-checked each DLC) and hit play, but still the Download button would not click.

Thanks ahead of time.

What mods (if any) are you using in your game? Also, I don't believe the download button has anything to do with the DLC. Once you have activated the DLC in "Data Files" you should see a message in the upper left of your pip boy alerting you to a radio message.