I just got my iMac a few days ago. Previous owner said he removed everything that was his and cleaned it all but the messages icon keeps updating in real time because it's still connected to his iPhone. I am running Mountain Lion on it. I'm pretty unfamiliar with anything Apple right now but I am getting the hang of it. Just so I can be at a bit of ease, this guy can't see my information on this computer now can he? How can I disconnect this iMac from his iCloud account completely and have just my own. All I own is the Mac and an iPod, that's all I want connecting to each other under my own account of course. Any ideas as to how I can fix these issues would be great! Yes I'm a Newbie but I know I'll be here a lot cuz I'm taking Graphic Design and this new OS is VERY new to me now and I need to know it like the back of my hand (or like my Porky PC that crashed for the last time, never again!) Thanks!