How to fix Mac Format & Partition Disk Utility Error " Erase Operation process failed. Click done

Sometimes a Disk Utility Error Message flags up when formatting or partitioning in Mac ( Mac Book Pro, iMac, Mac mini, Mac Pro, MacBook Air) which is asymptomatic of the HardDrive already engaged in operation and needs to finish before processing the next command to get past this we would need to forcibly unmount external hardDrive in Terminal by inputting some commands. See video which exemplifies how Terminal is initiated and the commands are applied to forcibly unmount the Drive which debugs the error message to zero errors and zero warnings.

CODE inputted in Terminal: Step 1: diskutil list Step 2: diskutil unmountDisk force Step 3 /Dev/ Disk 2,3,4,5 which is a variable.

Type in

terminal
spacebar diskutil spacebar list
(just take note of " /dev/disk2 " and dont type in just yet - depending on what your external hard drive references , in my case its disk 2 in yours could be disk3, My WD elements is the second disk)

now continue typing in

clear
diskutil spacebar unmountdisk spacebar force spacebar /dev/disk2
hit enter on your keyboard

Click the links below for use tips on how to

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