Hi, My machine is 15" Mid-10 MacBook Pro. I'm trying to upload a large youtube video which takes a long time. In Preference, Energy, I set the computer to never goes to sleep when on power adapter. I also unchecked the 'put harddisk the sleep whenever possible'. I also have the computer plugged in. But the computer would suddenly goes to sleep despite me telling it to never goes to sleep. second try, I downloaded Caffeine and set it to never sleep. my computer still ****ing goes to sleep. i just want to upload this one video whats its problem? Please let me know.