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Mac OS X 10.8 won't boot

HI there,

i'm trying to get an iMac running OS X 10.8 (Mountain Lion) to boot up again. It was constantly freezing up with the a continous spinning wheel so i was recommended to "Repair Disk Permissions", after doing this it will not boot back up again. It boots into recovery mode, asks me which language i want to use then i get
OS X Utillities -
Restore from Time Machine Backup
Reinstall OS X
Get help online
Disk Utility
There is no Time Machine backup so i opened Disk Utility and ran the various verify/repair disk & have included screenshots of the results.
I also ran diskutil list from Terminal & included the screenshot aswell.
I guess first think i'd like to know is if it's possible to back up my files from here & secondly is it possible to get it to boot up again without reinstalling. Also is this a sign that the hard drive needs repalcing?
I'm a novice with Macs & OS X so be as detailed as possible please & as always all help is much appreciated.
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bbaoIT Consultant

it seems like you got only a single partition on the 1TB drive of this iMac. correct?

how much free space does the drive have now?


As far as i know there is just 1 partition, it's not actually mine.

Disk Utility isn't giving me the Available, Used or Number of Files just the capacity - 999.35GB.

IMG1203 has the diskutil list.
Peter HutchisonSenior Network Systems Specialist

I suggest getting hold of another Mac, connect the broken mac (in target mode) to other mac and then you should be able to copy off your profile and documents off the mac. Then you can do a clean install of Mac OS on the broken Mac.

If you cannot boot into target mode, try booting of a Mac OS Disc or a Linux Live disc to gain access to the Mac HD:
If you don't have another Mac, you can plug in an external disk, and install a new OS X onto that disk, then copy the data from the internal disk to the external disk.  When done, you can swap the disk, or just make the external disk the default boot disk.


i just bought an external hard drive  & have ordered an internal ssd 500gb drive which is due on Monday/Tuesday. Would love to get this backed up or fixed this wkend though.
Can you send me the step by step instructions to install OS X to the external drive & copy the files across first?
I've heard Discwarrior might be able to fix it but want to back up the files before i go that route.
Peter HutchisonSenior Network Systems Specialist

Note installed MacOS to a external drive is the same as installing it on main HD. Boot from the DVD or USB drive and as part of the installation procedure, you get prompted to select which disk or partition to install the OS onto, it will show up and select the drive as the destination and proceed as normal.



Ok, so i have it up & running off the install off the external drive but how do i now copy & paste the files from the old malfunctioning unbooting hard drive to the external usb drive?
While you're booted up from the external drive, the internal drive should show as a disk on the desktop.  You can run Migration Assistant,app to attempt to migrated your data over, or you can open the disk manually and drag and drop copy the files.  Migration assistant will attempt to copy the settings from the other system, if it's been updated to the same version of OS X.  Drag and drop only copies user data, and no applications and installed settings.


Unfortunately the internal drive doesn't show up on the desktop or under Computer\Devices list. I can see it in disk utility though.
They're both running the same version of OS X, 10.8.4.
I'm trying migration assistant now, it's been looking for other computers for a while now but i'll just leave it run & report back with the results.
Peter HutchisonSenior Network Systems Specialist

Use the First Aid feature in Disk Utility to ensure the volumes are not corrupted and healthy.
Alternatively, open terminal run 'df -h' to list volumes, and run fsck device on it to do a filesystem check.
Try remounting the drive using mount device to see if it mounts ok (to dismount use the umount command).
Your disk may be dead.  If you really need the data, you may need to send it out to a data recover expert such as drivesavers https://drivesaversdatarecovery.com/


Migration Assistant "looking for Computers for 8 hours now.

Trying to Mount the device does nothing, just doesn't seem to mount properly.
fsck makes no differnece.

@ Serialband - "Your disk may be dead."  Think you might be right, lots of suggestions are leading me to try  Diskwarrior, anyone any experience with this software?

Getting sucktion cups in the morning so will try & take out the hard drive & run Seatools form DOS on a windows pc.

How tough are the screens, i bought 2 glass holding sucktion cups, they won't crack the screeen will they?


Seatools found multiple errors on the hard drive so i replaced it with an SSD & reinstalled.