Today a friend of mine came over with his 360's hard drive because he doesn't have Xbox Live or Access to the internet. We attached his HDD to my 360 and set him up with a 30 month XBL trail then used his key he got at gamestop to download Downguard.

Once it finished we booted up the game, got an update and then when we got to the menu we seen add-ons and made an new character and played.
He saved the game went back to his place and the game isn't showing up. This isn't happening because we downloaded it on my 360 is it? (using his hard drive though)

Does he have to have Xbox Live to play it?

Is the Add-On pop up coming up when you start the game?
If it is, then it may be because your new character is not level 10. That is the onlyrequirement to start Dawnguard.

I'll have to check tomorrow as it's late now and he's out of town. But hypothetically speaking, if Add-on isn't popping up like it was on my console what could be the problem? I don't think using the HDD on different consoles could be the issue could it?

That is exactly the problem. Using someone elses HDD in your system means that its YOUR xbox's hardware code that is attached to both the xbox live account and the DLC. Never put someone elses HDD in your system, you can royaly frak up their xbox when the HDD is re-attached, especially if they dont have xbox live to get the dashboard updates required for some content. Hard drives are not unique so when content is downloaded the LIVE system uses the actual xbox's hardware code to register ownership and ignores any on the HDD.

What your pal will have to do is a licence transfer to authenticate the game for HIS xbox, not yours.

http://support.xbox.com/en-GB/xbox-live/marketplace-and-purchasing/download-content

Well we updated his Hard Drive before downloading as well. What a cluster f****. :S

Will he need to have Live to do a licence transfer or will he have to bring it back over?

ya always have you friend bring over his console with the harddrive, done stuff like this before and its a pain to get sorted out.

I hate DRM... isn't technology supposed to make our lives... easier?