My sister's Macbook Pro Retina won't shutdown or restart correctly. When you try to do either through the main menu the menu bar itself disappears but the macbook won't shutdown. You have to hold down the power button to force it to shutdown. I have already made a genius bar appointment for it and the macbook is within it's original 1 year warranty and it has Applecare+ on it. I'm wondering if it's a software issue as my Macbook Pro Retina (Same model as my sister's one) had the same issue for a short while but fixed itself after I did a software update. My sister's one is already on the latest version of el capitan so, I can't just update it.