how to fix corrupt hard drive

John, my Mac (2011 2.7 ghz intel core i5 vintage, running OS 10.11.6) has just developed an issue and will not shut down without me 'forcing it' to. I have run Disk Utility and the output tells me "The volume Macintosh HD was found to be corrupt and needs to be repaired."

I hate to admit it, but that does not sound like a job for me as I am not that tech savvy. I can follow instructions...

Does this mean a trip to my nearest Apple store and a repair / replacement of the drive? Is that even possible? Could it be something other than the drive hardware being faulty, ie software?

All my data is backed up, thank God. Any help / direction would be gratefully received.

a drive that fails to erase is not a drive you want to trust to your precious data.

a replacement drive is called for, and an external enclosure to hold it while you install MacOS X on it and get it all set up the way you like.

Then any problems you have swapping in a known-good, working drive are limited to issues around that surgery, and not a dozen other possible issues that can be impossible to isolate.

This sort of problem is generally not a hardware issue so your drive would normally not need replacing. A Genius at the Apple Store could look in to it but you could also try dealing with it yourself.

If you boot from the RecoveryHD partition you can then run Disk Utility and tell it to 'repair' the Macintosh HD volume. Disk Utility is not always successful it depends on the level of damage to the catalogues of the volume.

To boot in to Recovery HD see - About macOS Recovery - Apple Support

To use Disk Utility to repair your drive see - Disk Utility for Mac: Repair a disk using Disk Utility

It is possible to buy various third-party tools to do similar repairs and DiskWarrior works in a different way, rather than trying to repair the damage it builds a brand new catalogue from scratch. This approach therefore sometimes is more successful. See https://www.alsoft.com/DiskWarrior/

John

Just wanted to say thank you for your help. Fingers crossed, following the Disk Utility and Recovery HD guides seems to have done the trick.

Richard

The most common reason reformatting fails is because the hard drive has a hardware problem. Reformatting cannot fix hardware problems. As Grant says if the drive has a hardware problem you do not want to trust it with files as it is only going to get worse.

The fact you claim to have tried reformatting it and it fails implies you can see the drive listed although since the reformat fails it will only list the drive itself and no volumes on it. Volumes only appear if the formatting succeeds.

John - many thanks. I will spend some time on this and see if I can repair, otherwise I see a trip to a Genius Bar in my future....

Regards

Richard