#Mac partition cannot unmount disk how to
#Mac partition cannot unmount disk mac os
#Mac partition cannot unmount disk password

If you can't erase Macintosh HD, follow solution 2 to format it in Internet Recovery Mode. Once First Aid completes, try to format the drive again. Click First Aid at the top, then hit Run.Р”Вepending on your drive size, amount of data on it, the potential number of errors, the time First Aid takes for a diagnosis varies.Launch Disk Utility and select your Mac hard drive from the left sidebar.Running First Aid to repair Mac hard driveР’В could potentially fix errors that stop Disk Utility from erasing it. Solution 1: Repair the startup disk with Disk Utility First AidР”Р‡irst Aid is often used to scan the whole disk for errors relevant to the directory structure and formatting, then repairs it automatically. Format the drive in Internet Recovery Mode Repair the startup disk with Disk Utility First Aid But if that's your case, here are the solutions you can try. It's rare to see Disk Utility can't erase Macintosh HD in Recovery Mode. What to do when Disk Utility can't erase Macintosh HD? Nevertheless, If Disk Utility still can't erase the Mac hard drive, please repair it with First Aid. But, if you did choose the volume and still failed, you can click View > Show All Devices to display all the drives, then erase the drive itself to see if it succeeds. We recommend you erase the volume but not the entire disk to avoid the 'Secure Disk Erase Failed - Couldn't Unmount Disk' error. Then keep the Scheme as GUID Partition Map.

#Mac partition cannot unmount disk mac os

Name the hard drive (like Macintosh HD), choose APFS for macOS 10.13 or later Mac OS Extended for macOS 10.12 or earlier.

Select Macintosh HD, then click the Erase button.

Ignore this step if your Mac is running macOS Mojave or earlier.

Select Macintosh HD - Data, click the (-) sign, then tap on Delete to confirm the deletion.

On the Utilities window, select Disk Utility.

#Mac partition cannot unmount disk password

Select a language, then your account, and enter the password for it.On an M1 Mac: Turn off your Mac, and press the power button until you see the Options Menu. On an Intel-based Mac: Restart your Mac, then hold Command + R keys until the Apple logo shows up.

That's because you can't erase the drive you are currently running from, and you need to boot into Mac Recovery mode to format the Mac startup disk. If you are trying to format the Mac hard drive or its volumes - Macintosh HD and Macintosh HD - Data, you will inevitably see the Erase button grayed out in Disk Utility.

#Mac partition cannot unmount disk how to

How to fix the Erase button grayed out in Mac Disk Utility? How to fix the 'Erase process has failed' error on Mac? Here, we will discuss solutions to solve these Disk Utility erase errors so you can format the disk. You may fail to format your Mac hard drive or an external hard drive when the erase button is grayed out on Mac Disk Utility or when you receive the 'Erase process has failed' error message. What to do when Disk Utility won't let you erase SD cards, USB drives, and other hard drives on Mac?