I had the exact same problem. Now its gone..
I didn't see any repair option when I had this problem so, that might fix it :/ But the only thing i did was that I reinstalled BF3. Nothing else really.
A Complete uninstall before, and then reinstall. Now I can change the settings how ever I want.. atleast for now
Sucks to download the game again in 1MB/s tho. So beware, might take a while in this "just been released"-craze!
I'm having another problem tho, and i'm not 100% sure its BF3 related or just my Rig.
But BF3 is playing fine in the beginning and then gradually the performance gets worse, until its barely playable. I was thinking it might be memory leakage, but what can you do to fix that??
Is it possible its the Game? Is it Punkbuster?Edited by Abacuz - 10/27/11 at 2:22am