It looks as though there's a problem with the PC version of Fallout 3's latest downloadable content add-on, Broken Steel.
According to early posts on the Bethesda Softworks forum and our own experiences here, the DLC downloads and then throws up an error. […]
Bethesda has been in touch to update us on the PC version: "We're seeing the same error, which is a Games for Windows Live DRM Install error. Microsoft is working on fixing it, and we'll let everyone know once we've verified it."
So what new things will be introduced with Broken Steel?
Broken Steel presents the player with several new things. First and foremost, we’ve removed the ending of the game as seen in Fallout 3 and created a smooth transition to a set of brand new quests that picks up right where “Take It Back!” left off. In addition to that, the game no longer ends after the Main Quest… you’ll be able to adventure through the Wasteland as long as you wish. Second, we’ve raised the level cap from 20 to 30 to help accommodate the fact that the game no longer has a finite ending. Third, we’ve provided a large amount of new content to the game to keep the challenge level high for upper-level players: multiple new creatures and NPC types, new weapons, new armor, and new perks. Last but not least, we altered parts of the Wasteland to reflect all the changes that occurred due to the player’s actions in the Main Quest with new encounters, additional “Water Quests” and new locations.