A few months ago I replaced my hard drive at the advice of an Apple Genius. When I was told to replace it, I was having issues with my computer not loading, getting the grey progress bar and disk utility not being able to repair it. I was lead to believe that by replacing the HD, these issues would be solved. Unfortunately, this is not the case since I am now experiencing the same problems that I had before. Before going back to Apple, I was curious as to if anyone would have any ideas of what other ways this could be caused. Thanks for any replies.