I am trying to diagnose my MacBook Pro 13" Unibody which I bought in 2009, a little over a year ago. I got the infamous flashing question mark folder and ended up buying a hard drive enclosure to see if the hard drive was the problem, or something else. Anyway, I ended up being able to boot up from the hard drive when used in the enclosure yet when running the Apple Hardware Test, both the simple and in depth tests, it found nothing wrong. My fear is that this means the Logic Board has suffered some sort of failure. Has anyone here experienced this or have any ideas of if I'm right or if I'm overlooking something? I've searched the forums but wasn't able to find anything.