Not shutting down, blue screen hangs indefinitely
It seems like a persistent problem, has happened for the last 5 times I tried to shut down, I tried waiting for half an hour but the blue screen woudn't go, I end up having to hold the power button to switch it off. I even tried resetting by holding cmd+alt+P+R but that didn't solve the problem. Any other ideas?
Thanks.
MacBook Pro 17, Mac OS X (10.6.7)