Connecting external display turns both screens black

I updated from 10.8.1 to 10.8.2 for my MacBook Pro Retina with my external 27" Thunderbolt display. When I connect to my Thunderbolt display both screens are black. I can only see my mouse pointer and sometimes little boxes of display. Any idea what's wrong?


Solution 1:

The solution explained in this Apple Discussions thread worked for me.

  1. Delete /Library/Preferences/com.apple.windowserver.plist.
  2. Delete ~/Library/Preferences/ByHost/com.apple.windowserver.XXXXX.plist.
  3. Reset NVRAM.