You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Disk Utility Erase process failed: couldn't unmount disk, in use by process

Help. I am trying to erase my iMac (21.5-inch, late 2021, running OS Catalina) before I give it away or sell it, following the Apple instructions here: Use Disk Utility to erase an Intel-based Mac - Apple Support


I've encountered this problem and I can't figure out what to do next. I'll appreciate any suggestions. I'm not super tech savvy, so please keep it simple. Thank you.


iMac 21.5″, macOS 10.15

Posted on Dec 27, 2024 12:42 PM

Reply
3 replies

Disk Utility Erase process failed: couldn't unmount disk, in use by process

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.