I have a MacBook Pro 17" (Early 2011). It's been working well and the hard disk has not been exhibiting any problems ever. Until now it seems. I upgraded to Sierra (from El Capitan) through the Mac App Store, it downloaded it, restarted to install, but then it says:

"OS X could not be installed on your computer

File system verify or repair failed.

Quit the installer to restart your computer to try again"

However, each time I retry the same thing happens. Someone on another post I found that was similar said to start up using Cmd-r (holding while it restarts) to go to OS X Utilities, and then Disk Utility to repair the disk.

However, when I try to run First Aid on my internal Macintosh drive, it fails. One of the things it says in the log is "The volume Macintosh could not be verified completely", then a few lines below "File system verify or repair failed" then "Operation failed".

So what can I do? I do not have any back up, or an emergency disk or start-up disk. I have never come across a problem like this before.


If a First Aid operation on a drive is failing, in my experience, the drive is almost certainly toast - the fact that it happened after trying to upgrade to Sierra is just coincidental, or it touched a part of the drive that was already marginal.

I'm afraid that your machine is dead until such time as you get the drive replaced. 2011 MBPs are fairly easy to work on, and replacement drives are cheap. Once you get one, you'll do the recovery boot process just like you did before, but hold shift - this will get you into internet recovery, where you can download a fresh copy of the OS.

As to getting any data off the drive, it depends on how dead it actually is. Your system isn't hanging up, it's just failing to verify, so you very well may be able to connect it to another machine and pull your data off.

There's also a commercial product, DiskWarrior, that I've heard stories of recovering problems like this, but it's fairly expensive ($120 US) - weigh this against the cost of whatever data's on the drive.

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    DiskWarrior is well worth the money, but as part of an armoury of complementary products; Disk Drill, TechTool Pro, Drive Genius etc. None of them will guarantee you get your data back, but having a swing at the drive with them all is as good as you'll get without sending it to a recovery company. Your wallet, your call ;) First test would be see if you can repair the drive by booting from a USB key - much easier to work on a drive you aren't booted from. Of course, nothing replaces having a current backup ;) – Tetsujin Apr 2 '17 at 12:58

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