I had the very same problem. Here is how I solve it (sorry it's a bit long but details are important to solve a problem).
First, Awakening is not a DLC. It comes with DAO - Ultimate edition. It's on the DVD. I suppose it's the same if you downloaded it. If you have installed DAO, then you have installed Awakening. No need to download anything else, and no need for another code than the one to install DAO (I mean, for Awakening, I'm not speaking of "Leliana's song", "Witch hunt" etc ...)
I guess the problem occurred (for me) because I installed DAO in a user profile (on windows 7) and played in another. In the user profile I installed it, Awakening was available, both in “Other campaigns” and when starting a new game, but not in the other profile.
If you are in this case, then maybe the following can help.
I found the solution here:
http://forums.steamp...d.php?t=1566158, but it was not very clear (to say the least) so I rewrited it below. The files paths are those of windows 7.
The procedure implies editing the file “<userprofile>\\Documents\\BioWare\\Dragon Age\\Settings\\AddIns.xml”, so MAKE A BACKUP COPY OF IT BEFORE DOING ANYTHING ! And quit the game.
You need to open the same file (or a copy of it), but from the profile you used to install the game (right click/edit). Select the section beginning with <AddInItem UID="DAO_PRC_EP_1" and ending with the first </AddInItem> that follows. There's about 200 lines. Copy that, and close the file. Don't save, if you are asked to (you shouldn't).
Now open the AddIns.xml file in the userprofile you use to play, and paste that section at the end of it, just before the last line (</AddInsList>). Save it.
Now you should have access to Awakening.
Modifié par Khrys41, 26 février 2011 - 07:06 .