Can't reinstall macOS on M3 iMac

Question

Can't reinstall macOS on M3 iMac

I recently noticed that macOS on the M3 iMac was a bit unstable, so I tried erasing it and reinstalling macOS. I went to recovery, then erased the APFS volume group that contains the macOS data volume. However, when I tried reinstalling, it displays an error saying that I needed to erase the Mac first. Keep in mind, I already erased the APFS volume group. I tried erasing the device instead from Disk Utility (Command+Shift+2) then selected APZ xxxxxxxxx Media, but it wouldn't unmount because the kernal was using it. I tried this with both a USB installer and Internet Recovery, force unmount and erase from Terminal, and also many restarts, and power connects/disconnects.

iMac (M3, 2023)

Posted on Jan 24, 2024 6:58 PM

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Answer 1

PRP_53

Level 10

91,477 points

Jan 25, 2024 2:11 AM in response to AppleSilicon_Gamer

The M3 iMac was released Oct 31, 2023.

It may have come pre-installed with a Special Version of Sonoma which was specific to support the M3 machine code.

Erasing an Apple Silicon computer is more complex than the old way on Apple Intel machines.

At this point you may or may not need to either Revive or Restore the computer

That may required this method from Apple

Revive or restore a Mac with Apple silicon using Apple Configurator

Suggest holding off a bit.

I do know several more expert contributors who may have other less drastic measures to try before going down the above rabbit hole

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Answer 2

PRP_53

Level 10

91,477 points

Jan 25, 2024 5:04 AM in response to AppleSilicon_Gamer

I do see two more experienced contributors on this specific issue around

Let Us ( you and me ) hope they join your question with some insights or at least different directions before you move forwards.

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Answer 3

Jan 25, 2024 4:51 AM in response to PRP_53

Thanks for the reply! I have been holding off on reviving with the configurator for a last resort solution. I think it has come to the point that I need to use configurator.

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