Re: finding dlc in explorer

DLC are stored in a subfolder of your ME3 install.  The typical folder structure:

Origin Games\Mass Effect 3\BIOGame\DLC

Citadel is in TWO folders:

DLC_EXP_Pack003

DLC_EXP_Pack003_Base

One of these is the "free" part 1/2 install.  Don't recall which.  And not sure why they did this since you need BOTH to run.

To see where Mass Effect 3 itself is installed to, from Origin client > Origin (in Menu)> Application settings>installs & saves tab, which has:

On your computer - Game library location

(unless you changed this after you installed ME3)

default is, I believe: C:\Program Files (x86)\Origin Games

But if Origin keeps trying to download ALL of them, that seems to suggest some other issue.  Like did you change your games install folder?