Mac can't detect external display after update.
I recently updated my MBA, i forgot what update it was but it had safari 6.0.4 in it and a few somewhat minor updates but after the update my Mac can no longer detect external displays. I tried restarting, removing, and turning off the TV but it still wont work. Before, I just had to connect the cable and the mac instantly recognizes the display and it quickly switches to that but now it wont work. Is this a software problem?
MacBook Air, OS X Mountain Lion (10.8.3)