Hi all, My co-worker has an issue that has me stumped. He has a 2011 MBP. As of this past weekend, every time he attempts to use his computer, he'll turn it on, and it will show the grey boot-up screen with the Apple logo, and then will change to a black screen. The funny thing is, he can see his mouse pointer on the screen and move it around, but he's stuck at that black screen. He says his keyboard backlights still illuminate. He's tried booting into safe mode (worked once) and holding option-R, but that hasn't worked. Any ideas what the issue might be, and what he can do to fix it? Thanks!