ArmasTermin
A friend at work gave me the DLC disc for Operation Anchorage and The Pitt. I loaded it onto the machine (and got the spiffy new 360 look) but the insert with the disc said I'd get a prompt that the new quests were available and... I didn't get it. I don't know what I can do to make it happen.
Is this on PC or 360?
If on 360 the content probably wasn't loaded because it was used on another machine.
Are you connected to xbox live?