My iMac is about two years old. Suddenly for the last few weeks it has given me problems booting. I have Bootcamp partitioned and run Windows7. The problem seems more on the Mac boot side than Windows but can be both. I noticed lately when it closes down it takes an inordinate length of time while running File Vault. "Recovering disk space in my home folder" can take two or three minutes when it use to fly though. I wonder if the recent update to Bootcamp affected the boot process? I usually get the gray screen and the mouse pointer just sits there. I've tried all the steps in the forum...safe boot, holding the C key, and the four specific keys at once. None of them will bring it out of the funk. This always seems to happen once the computer goes to sleep. If I try repeatedly to re-boot I cannot get anything to work. If I leave it alone for a few hours it will boot just fine. If I set it to boot in Windows (bootcamp) that is always a problem and if I am in Windows and click on the re-boot in Mac it will never work properly. I have no idea where to begin. I ran the diagnostics on utilities and nothing comes up.