Unmount external disk with disk utility fault

Could you tell me what to do on disk utility when it fails to unmount the disk?

(disk could not be deactivated. : (-69888)

MacBook Pro 13″, macOS 13.2

Posted on Mar 30, 2023 2:52 AM

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2 replies

leroydouglas

Level 10

206,698 points

Mar 30, 2023 5:23 AM in response to Sier

Sier wrote:

Could you tell me what to do on disk utility when it fails to unmount the disk?

(disk could not be deactivated. : (-69888)

You can try the Terminal.app copy and paste:

diskutil umount

notice the trailing blank space, drag and drop your external drive onto the Terminal window to complete the path.

Use the enter\return key to proceed.

Sier Author

Level 1

17 points

Mar 30, 2023 7:30 AM in response to leroydouglas

Thx !

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Unmount external disk with disk utility fault

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