There was an error while downloading the content list for your game.
This is the error I get when trying to download content for both Splinter Cell and Halo 2. I'm assuming that if you try to download content for any other original Xbox title, you will see the same error.
You see, I have this content already, and in the case of Halo 2, paid a pretty good chunk of change for it. Thanks to Microsoft's wonderful hardware quality, I've had to purchase a new Xbox 360 (kept my HDD) and now all of my DLC is corrupt (presumably linked to my old 360.) Lovely.
Microsoft, you're killing Xbox Live for the original Xbox in April, not February. Give us a chance to download original Xbox content before the cutoff date.