I finally upgraded to Mavericks when 10.9.2 was released, on my Mid-2011 27" Imac. All has been working well except that the computer will not go to sleep. The screen saver will activate and the display will sleep but the computer itself still remains awake. I can force it to sleep from the apple menu, but it will not do it by itself. Yes I have checked my energy saver settings in system preferences, and all is good there. It would go to sleep fine in Mountain Lion, but never in Lion(again for some odd reason). Nothing in my configuration of the machine has changed other than the Maverick upgrade. Any ideas?