iMac with corrupted catalog

[lefty2]

Hi all,
I have a 2010 iMac with suffered a power failure on start up and this has seemed to corrupt the catalog drive. It has OS X 10.11.6 and bootcamp partition. Now the Windows partition boots up fine and can even see the Mac partition from file explorer, so I don't think there is anything physically wrong with the drive.
So far I have tried the following:
* boot up in recover mode - gives the no access icon
* boot up in network recovery - the same
* booting up with a recovery flash drive - boots up fine but cannot see the hard driver, therefore cannot install anything
* booting up with the original OS X install DVD - boots up fine but cannot see the hard drive
* boot up in single user mode and try and repair with fsck and fsck_hfs -rc -d /dev/disk0s2 - hangs forever rebuilding catalog
* in single user mode and try "/sbin/mount -uw /" then "exit" Gives error disk0s2 media is not present

Is there anything else that I could try, or should I just give up at this stage?
I am grateful for any advice you can give,
thanks
Ed

 

[DeltaMac]

Have you tried any other disk directory tools, such as DiskWarrior? Your symptoms sound like a typical corrupted directory, and Disk Warrior should do a good job fixing your directory...

You also said that booting to Windows - you can see the Mac partition in file explorer? That doesn't really make sense on a normal Windows, as Windows won't usually see any files on an HFS-formatted drive.

Just as an experiment, boot to your bootcamp/Windows system, and try to look at files on your Mac partition, particularly in your /Users folder. I suspect that you won't be able to see any directory on your Mac drive (and you should not, unless you have something like MacDrive installed on your Windows system. )

If all of this does not get you any success -
Do you have a current backup for your OS X boot drive?
Boot to your installer flash drive, and erase the drive. Reinstall OS X. Restore your apps and files from your backup.
If you DON'T have a backup, it may be too late for that (particularly if Disk Warrior does not help...)

 

[lefty2]

Hi DeltaMac,
Thanks for the answer.

Have you tried any other disk directory tools, such as DiskWarrior? Your symptoms sound like a typical corrupted directory, and Disk Warrior should do a good job fixing your directory...

Yes, I created a DiskWarrior recovery disk, but as I said before recovery disks don't work, because they cannot see the internal drive. I don't know why.

You also said that booting to Windows - you can see the Mac partition in file explorer? That doesn't really make sense on a normal Windows, as Windows won't usually see any files on an HFS-formatted drive.

Just as an experiment, boot to your bootcamp/Windows system, and try to look at files on your Mac partition, particularly in your /Users folder. I suspect that you won't be able to see any directory on your Mac drive (and you should not, unless you have something like MacDrive installed on your Windows system. )

Hmm, I thought Bootcamp installed drivers that let you see the Mac partition. Yes, I can see /User folder and most of files on partition.

If all of this does not get you any success -
Do you have a current backup for your OS X boot drive?
Boot to your installer flash drive, and erase the drive. Reinstall OS X. Restore your apps and files from your backup.
If you DON'T have a backup, it may be too late for that (particularly if Disk Warrior does not help...)

As I said before, if I boot on a recovery drive or DVD it can't see the internal HD, so nothing is posssible

 

[DeltaMac]

Your power failure might have corrupted the SATA-drive controller (booting to Windows may communicate to the controller with different protocols, and may explain why Windows boots
Then, try a few different ideas that sometimes work (sometimes not)

Reset NVRAM: Power on, while holding Option-Command-P-R
You should hear a boot chime sound. Continue to hold the same 4 keys until you hear the boot chime 2 more times, then release the keys.

After doing that, try booting to your DiskWarrior recovery disk.
If you don't see the system disk listed, it's possible that even the name of the disk is corrupted, so might be invisible in the list. Make sure, by clicking on the first available space in the list of possible drives to scan, that a blank is actually a disk. (I have seen this once or twice.)
Of course, even that should show up in Disk Utility, even if there is no name.

I would then choose to connect an external USB drive with a bootable system. I have three or four, and usually go for a Yosemite system. It's a full install, not just a bootable installer. It's also another way to use Disk Utility (from a fully-booted system).
If you still can't see the drive in Disk Utility, go to the System Information. How does your internal drive show up in the SATA tab? Do you see your system partition there?
Then, next step is to remove the hard drive. You can do that on a 2010 iMac in less than 10 minutes. Test the hard drive in an external case.
(This will also give you access to replace the PRAM battery, which can sometimes cause really strange issues, if it is dead)
Replace the hard drive with an SSD (as a recommendation), installing that in your iMac. Install a system on that. (Lots of advantages to doing that, anyway)
Assuming that the drive controller is working, that should fix you up.

 

[lefty2]

Ok, I tried the Option-Command-P-R, but it didn't make any difference.
At this stage I think I'll just give up. It's not worth spending any money on a old machine like this. Thanks very much for your help anyway,
cheers,
Ed