Think of it this way your shoes heel broke off and your stop by a shoe cobbler how is he going to fix your shoe? You need to take it off right! Thats the same here if you want to reformat the drive you need to boot up under a different drive to release the drive from the OS. When erasing it says “Erase process has failed” with details saying “Couldn’t unmount disk - Operation failed”.Įither make the encryption in FileVault to continue the progress which didn’t work after reading about it and trying things… or to erase the HD and start a new install from my Time Machine backup. I tried to repair or erase “Apple HDD HTS547575A9E384 Media” but it does not work. on Disk Images I see “Apple disk Image Media” which is 2.01 GB and has under it “OS X Base System”(1.29 GB) with option to eject which does not work.

In Disk Utilty I see under Internal “Apple HDD HTS547575A9E384 Media” under which is greyed out my “Macintosh HD”. Now I can not even reformat the HD using Disk Utility from CMD+R mode. I decided to reformat my HD to make a clean install(I have backed up the system with Time machine) after Disk Utility have failed to repair the disk. I think the problem might be something with repartitioning the HD but I see others have problem with encryption as well. After that I went to encrypt my HD using FileVault and it got stuck for days at around 60%. I am running Macbook Pro (Late 2011) on Sierra osX.įirst I repartitioned my HD into single partition(I had Bootcamp).

Erase process has failed mac