These addons unlock new areas to discover, such as the Soldier's Peak or new characters and their backstories such as Shale. They can still be obtained - either by buying a new copy of Dragon Age: Origins or through the in-game interface with BioWare points, Microsoft points or through the Playstation Store.
There are a few in-game bugs that restrict a player from downloading his or her content. These instructions are meant to help PC players manually install their authorized DLC. Downloadable content can be manually installed in the PC version of Dragon Age: Origins. However, some downloadable content, such as Warden's Keep, requires authorization. As such, they cannot be enabled in-game until they have been authorized - either by entering a promotional code or by purchasing the content.
To install downloadable content manually follow these instructions:
Be aware that a majority of the DLC requires an active internet connection and also requires you to be logged into your Bioware/EA Online account that you used to purchase or redeem the content. Otherwise you will get Unauthorized info in the Installed Content.
The Stone Prisoner, Warden's Keep, Return to Ostagar, The Darkspawn Chronicles, Leliana's Song, Golems of Amgarrak, Feastday Gifts, Feastday Pranks and Witch Hunt require the corresponding offer files to work. The installation procedure for offers is the same as that for any other DLC.