Unibody MacBook Pro models with 13" displays produced from 2009-2012.

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Data extraction from partition showing prohibition sign on boot


I have a MacBook Pro mid 2012.

Yesterday I updated both my internal disks, an SSD and an HDD, from El Capitan to Sierra; after rebooting, the HDD started showing up a prohibitory symbol after logging in and the loading bar is almost full.

I tried everything, from Disk Utility to booting into Single User Mode and using fsck, to running data recovery apps, to trying to rebuild the OSX volume - but got nothing.

The disk doesn't have any physical problems, itself, seeing as both the Windows and Linux partitions on it still work and boot. Also, checks with other apps rule that out, too.

My question now is: is there any way to make that OSX volume bootable or mountable again, so I can access my files for a backup? I have 100GB+ of Photos Library that I'd be pretty angry to lose. Maybe I could go about creating an image, somehow, of the partition, hope my files are on that? But how, if the volume doesn't mount?

I can't fathom how this can happen after a simple update, and I also can't fathom how I never thought to backup my photo library...

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Try booting into recovery mode by holding down the option key on start up and run disk Utilities. Never do a system upgrade without an external backup. BTW this is your only protection from Ransomware attacks.

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I tried that, no success. The drive shows up unnamed and it can't be mounted nor fixed.

When I try to mount it, it says: "unknown special file or file system" and when I try to run First Aid on it I get:

"File system check exit code is 8.

Updating boot support partitions for the volume as required.

An internal error has occurred."


Since this happened while doing an Apple System upgrade, Apple is obligated to help you. Call 1-800- MYAPPLE and get a senior advisor.


I live in Italy and my warranty expired, I didn't want to go to an Apple Store and waste a lot of money... I'm assuming extracting the data from a drive is a costly operation.


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