#Disk erase failed couldn t unmount disk how to#
#Disk erase failed couldn t unmount disk install#
#Disk erase failed couldn t unmount disk mac#

While booting up, hold down the Option key to boot using the Recovery Partition. Use Disk Utility App to Erase and Format Convert the Drive Using a Bootable.

#Disk erase failed couldn t unmount disk how to#

If this is the case, you can try resolving the error using Recovery Partition. Part 2: How to Fix Could Not Create A Preboot Volume for APFS Install. Once this pops up, the current process gets halted and could no longer proceed, affecting any troubleshooting process or disk repair you might be doing. Volume Erase failed Volume Erase failed with the error: Couldn’t Unmount Disk. I've tried to verify/repair disk and, after a couple error messages ('This disk needs to be repaired' and 'Disk utility can't repair disk, erase it') I'm in the starting point. If the Couldn’t Unmount Disk error message appears when doing First Aid on your disk or formatting a non-boot disk, the first solution will not work. Disk Utility stopped verifying (letter of the hard disk) Couldn’t Unmount Disk. But it happens that when I try to erase the partition (Mac OS Extended or create new ones with disk utility I get the message 'couldn't open disk' or 'couldn't unmount disk'. Now everything is working fine with my computer and I wanted to format the external hard drive.

#Disk erase failed couldn t unmount disk install#

I used an external hard drive to install Yosemite (creating a single partition) and boot my computer from there, as I had a problem with my internal hard drive. and still the disk will not unmount! What should I do?īTW, here is the response in Terminal after the command diskutil list:Ģ: Apple_HFS Macintosh HD 499.2 GB disk0s2ģ: Apple_Boot Recovery HD 650.0 MB disk0s3 Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears.

This happens in a few circumstances, but most of the time because you’re trying.

Things I have tried: unplugging the HD and plugging back in, restarting my computer, restarting and holding command+r to enter disk utility, entering Terminal and typing ' diskutil unmountDisk force disk1', disabling Spotlight in Terminal (' sudo mdutil -a -i off ') then trying to force disk unmounting (above command and ' sudo diskutil unmountDisk force disk1') For instance, some readers report receiving the message: Secure Disk Erase FailedCouldn’t Unmount Disk. I can find the disk in Disk Utility, but cannot repair it, eject it, or unmount it when I try to erase and/or re-partition the disk. After disabling Spotlight, Disk Utility performed its job and my corrupted drive was restored to use. Specifically, I have a WD Passport external hard drive (formatted FAT) with a single partition that doesn't show up in Finder when I plug in the HD. Step 2: Type Disk Utility in the search field.

#Disk erase failed couldn t unmount disk mac#

Reboot your Mac and run Disk Utility First Aid 2. I am running Mavericks 10.9.2 and am having the same problem, but am unable to fix it with the help suggested by Kappy and Dr.Mac. Fixes to solve the ' Erase process has failed' error on Mac: 1. 3) Hopefully you can now perform your desired erase, partition, installation or deployment on this drive.