@redrew83The problem is with the EA crapapp. Just finally solved this from a description on Steam:
Move the entire game folder in question from the steamapps/common folder.
Go to the app in steam. select uninstall
Quit Steam
Got to the app in EA crapapp
From the hamburger menu, help, app recovery
When the EA crapapp reopens. Your game should no longer be listed.
Move the game folder back into the steamapps/common folder.
Open steam
Select the game and install
Steam will relink the files (rather than reinstalling/redownloading them)
Quit Steam
At this point I was able to play Mass Effect again.
If you can't, open the EA crapapp and see if it is there.
I may have forgotten something, and I apologize if I did. Good luck.
