machintosh disk format was failing

Disk utility was failing with error while formatting machinthosh disk . The error "disk can not be unmounted"

Posted on Dec 4, 2020 12:15 AM

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2 replies

HWTech

Level 9

69,338 points

Dec 4, 2020 8:10 PM in response to Maheswara

You cannot erase the drive if you are booted from it. To erase the boot drive you need to boot from some sort of external media such as Internet Recovery Mode or a bootable macOS USB installer.

John Galt

Level 10

155,810 points

Dec 4, 2020 3:51 AM in response to Maheswara

Disk Utility User Guide

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machintosh disk format was failing

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