Re-installing Mac OS after erasing disks

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Re-installing Mac OS after erasing disks

Good morning,

I have a MacBook Pro A1707 (intel chip) that I wanted to factory reset and remove all data from. I did this through the command line and probably messed some stuff up because I can't seem to re-install MacOS. My knowledge is very limited when it comes to hard drives, partitions, etc., and I'm pretty sure I messed it all up.

Attached are images of my disk utility and the errors I receive when I try to erase a disk or perform first aid on the disk. Also attached is an image of the error I receive when I try to re-install MacOS.

When I try to erase the disk through the command line, I receive a "Disk cannot be unmounted" error on every disk.

I know that there is a way to repair and format these disks correctly, but my knowledge just isn't there. I would like to use this as a learning experience, and any guidance would be greatly appreciated.

Thank you!

Images:

https://ibb.co/v3fVv6S

https://ibb.co/k60ybvp

https://ibb.co/s9nRRNC

https://ibb.co/vHRSV42

MacBook Pro 15″, macOS 12.2

Posted on Aug 28, 2022 11:06 AM

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Answer 1

Top-ranking reply

HWTech

Level 9

60,308 points

Aug 28, 2022 12:52 PM in response to Overthinkingit

You need to boot into Internet Recovery Mode (Command + Option + R) or by booting from a bootable macOS USB installer in order to erase the drive. You cannot erase the same drive you are booted from so you need to be booted from the OS installer.

If your laptop can still boot, then I highly recommend creating a bootable macOS USB installer so you have more options in case something goes wrong with Internet Recovery Mode. Here is an Apple article for creating a bootable macOS USB installer:

How to create a bootable installer for macOS - Apple Support

Here is another article on how to reinstall macOS (it references Recovery Mode, but the instructions are the same once you are booted to the macOS installer):

How to reinstall macOS - Apple Support

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