MacOS – Macbook Pro won’t boot into OSX (circle with line through it), but Windows works fine

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When I try to boot into OSX, after 30 seconds or so the Apple symbol is replaced by a circle with a line through it. If I try single user mode, it stops at a certain point before booting entirely and says "waiting for root device."

However, I was able to successfully boot into OSX after trying five or so times. Then, after running for a few minutes it froze up. I've been able to repeat this a couple times, but 90% of the time it just shows the circle.

I do not believe this is a hardware problem because Windows works fine (I am typing this from Windows), but it doesn't scream "software problem" because it's intermittent.

Any advice?

PS: I replaced the stock hard drive last year with this: http://www.newegg.com/Product/Product.aspx?Item=N82E16820171569

I found a blog post http://www.klein2.de/does-apple-drop-the-intel-x25-m-ssd-support-with-10-8-3/ that seems to describe my problem, but I doubt that it is for the same reason. The screenshot with the black background is exactly what I see when I try to boot into single user mode.

Best Answer

I brought it to the Apple store where they replaced the hard disk cable for free (possible thanks to Applecare). OSX works again. This solution defies logic to me; I didn't think it could possibly be a hardware problem because Windows worked fine.

I am including the relevant parts of their problem writeup below:

Issue: Mac OS partition boots to a prohibitory symbol. 
Windows partition can run fine
Occurred after waking from sleep, computer froze completely 
Steps to Reproduce: Observed at bar 
MRI passes, third party memory 
Booted to 10.8 installer and internal drive did not mount 
Booted to storage diagnostics and no hard drive detected 
Proposed Resolution: Replace hard drive bracket, has third party drive, run storage diags after bracket and see if drive is recognized
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