Stop sign on boot and unable to reinstall Mac OS X

[nessel]

Hello everyone,

This is my first time posting here, and I'm not sure if this is the right place for this thread. However, any help would be greatly appreciated.

I'm helping my brother with issues on his Mac since he is not very computer literate. He has a Mac Book Pro (2009), but he is not sure what OS. I know it is at least OS X 10.6.8, but he is unsure if he performed any updates afterwards.

It recently started receiving the grey screen stop sign when booting. We tried following these instructions http://support.apple.com/en-us/TS2570. After attempting the safe mode boot, a flashing question mark was present. Now when holding option to boot, none of the startup drives are shown. A blank grey screen is the only thing that appears. We tried following these instructions as well http://support.apple.com/en-us/TS1440, but we cannot view any startup drives.

I was able to create a bootable usb drive of OS X 10.10 and the installer loads up fine. The problem is only the flash drive shows up in disk utility and when attempting to install the OS. I tried a diskutil list in terminal, and the drives do not show up there either.

However, if I reboot from this bootable OS X installer and hold option, all drives are now seen again on the startup screen(Mac OS X, Windows, Recovery HD, OS X Installer). In fact, I am even able to boot into the windows boot camp startup (partitioned from the same drive as Mac OS X). Therefore, I do not think that the HD is broken.

However, trying to boot into Mac OS X or Recovery from here leads back into the grey stop sign. Any suggestions on how to get past this screen or how to get the drives to appear in order to reinstall OS X? I don't know what else to do at this point.

 

[nessel]

Update

So I was able to use a program called HFSexplorer in the Windows bootcamp partition to view the Mac OS X file system. I'm able to extract files from the Mac partition into the Windows partition.

So the hard drive definitely works right? I'm not very familiar with how the boot system works, but could it be that some files are corrupted? Anyone have any information.

HFSexplorer:

 

[Nermal]

Does it attempt to boot if you hold Cmd-V at the chime? If so, post a photo of the result.

 

[nessel]

Hi,

Thank you for your response. When I try booting and holding Cmd-V it takes me to the flashing question mark. This is the same result when I boot without holding anything.

When booting and holding option it just takes me to a blank screen. At this screen, if I plug in the bootable usb, the installer shows up.

If I enter the bootable installer and then restart from the installer menu holding option, all of the bootable options show up. This is how I was able to boot into Windows. However, trying to boot into Mac OS from there brings up the stop sign.

 

[Nermal]

If I enter the bootable installer and then restart from the installer menu holding option, all of the bootable options show up. This is how I was able to boot into Windows. However, trying to boot into Mac OS from there brings up the stop sign.

OK, try that again, but hold Cmd-V. Hopefully that'll give you the reason for the stop sign.

Having said that, it sounds like your drive could be on the way out

 

[Fishrrman]

My suggestion (my opinion only):

If you are still struggling with this, hunt down a copy of OS 10.8.5 "Mountain Lion". It "can be found" from sources -other than- "the official ones", if need requires.

See if you can get THAT to install...

From what I gather, 10.6 (Snow Leopard) "doesn't recognize" -something- about the drive formatting schemes used by 10.10. Probably has something to do with "CORE storage", which didn't yet exist at the time 10.6 was developed...