Couldn’t Unmount Disk error 69888

when i trying to make bootable usb for Mac osx Install OS X El Capitan i got this:Error: -69888: Couldn’t unmount disk

Community Answers

  1. 577
    10-25-19 says:

    “Couldn’t Unmount Disk” errors are relatively common, and they prevent users from formatting an internal disk or creating a bootable USB. The good news is that this issue is relatively easy to fix, simply follow the guide in our How to fix "Couldn’t Unmount Disk" Error on Mac? article.

    The error might occur due to several different reasons, such as corrupted hardware or due to the drive being used by other applications. Due to this, the remediation process for the issue may vary. Nevertheless, you should try all the solutions we provide in the above-mentioned article.

    Good luck,
    Ugetfix team

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