Problem

When I try to install a new expansion pack/stuff pack from Origin, I get the following error:

DLC Compatibility Alert

It seems the base game for this DLC was not installed through Origin. For <name of the EP/SP> to work, you will first need to:

1. Select Uninstall Now below, locate the base game, and follow the on-screen instructions to uninstall it.
2. Download and install the base game through Origin by selecting it in My Games and clicking Download.

After that you can download and play <name of the EP/SP>

Cause

Seems people that have the base game installed through the DVD get this message when trying to install the download version of one of the expansion packs. Be aware that is not necessary. You can very well mix the DVD version with the Origin download version (you can’t mix the Steam version with the DVD version though)

Solution

To be able to install the download version without reinstalling despite that message, do not click on the Download button in Origin, click on the “i” (information) button. This will open another window that also has a download button. Click on that to install.