olifromgb

Q: External Hard Drive won't mount after Sierra update

Hi there, I have a a external 1TB Segate HD that I with my MacBook Air. After upgrading to macOS Sierra, it refuses to mount and so is invisible to Finder. Disk Utility detects the drive as initialised NTFS and says all the space has been used. I tried first mounting it through disk utility, but it did nothing. I then tried through terminal, but it returned 'failed to mount'. It worked fine before and also works fine on a MacBook Pro running Yosemite. It can't be anything to do with the drive as all the files are intact when connected to the other Mac. Also, I restarted into Mac Utilities and ran the disk utility from there, and it detected the drive, mounted and fully initialised, with the correct amount of space being used up.

I am looking for a solution that doesn't involve copying files off and reformatting if possible, but I will give it a go if it comes to that. Thanks very much.

MacBook Air (11-inch, Early 2014), OS X El Capitan (10.11.4)

Posted on Sep 26, 2016 4:31 AM

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Q: External Hard Drive won't mount after Sierra update

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  • by Volunteer_Apple,

    Volunteer_Apple Volunteer_Apple Oct 12, 2016 10:12 AM in response to EcoGreg
    Level 1 (4 points)
    Mac OS X
    Oct 12, 2016 10:12 AM in response to EcoGreg

    I'm having the same issue with a WD USB Passport drive failing immediately after the Sierra upgrade.  I only use this drive for Time Machine backups and it has (had) a with Journaled Mac format.  The drive spins, the WD utility sees it and was even was able to update the drive firmware, and I can see it in the CLI drive utility list.  But, it won't mount or force mount in the CLI, the Disk Utility app won't discover it and it doesn't present as an available device.

     

    I think I had this issue before with a different major OS upgrade.  Is there a drive protection / upgrade process that I should do before future upgrades.

     

    Thanks!

  • by a_drummer,

    a_drummer a_drummer Oct 13, 2016 8:34 AM in response to olifromgb
    Level 1 (4 points)
    Oct 13, 2016 8:34 AM in response to olifromgb

    Thanks for the link - driver updated, all is well,

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