External Drive Unmounting

I'm trying to erase an external hard drive for use as a Time Machine on a MacBook Air (M2) running MacOS 15.1.1

Disk Utility reports that it cannot unmount the disk - in use by processing 112.

I have followed all of the restart and close all programs etc, advice that is posted, but it makes no difference.

I have the same problem on my M4 Mac Mini.

The external drives have USB A plugs, but as both machines have USB C ports, I am having to use an adapter.

Posted on Nov 22, 2024 3:10 AM

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Posted on Nov 23, 2024 1:56 AM

Sorted - albeit in a cumbersome way.

The disk was formatted as FAT32. I moved the files to the trash and emptied them.

I then removed the disk and remounted it.

In Disk Utility I was then able to erase and change the disk format to Apple File System.

A bit of a faff, but done

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External Drive Unmounting

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