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.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Deleting the Mac-Os Data Partiton

I have installed macOS Big Sur and due to bootcamp not working I need to downlaod macOS Catalina. I have found out that I need to erase the macOS Data partition when I boot into the installer so I can install Catalina. Is it safe and will I keep all my data (files, games, movies ect.)?

MacBook, macOS 10.16

Posted on Jul 20, 2020 5:47 AM

Reply
5 replies

Jul 20, 2020 5:59 AM in response to GourishRc

The Macintosh HD - Data partition contains all of your files and data, removing or erasing this will erase your personal content.


Since you are coming from the Big Sur beta back to a public release of macOS, you will need to completely erase the hard drive, including the Macintosh HD - Data partition. Obviously it is best to backup your data with Time Machine before carrying out any such process.


Click the Macintosh HD - Data partition in the left side bar, click Edit in the menu bar and then click Delete APFS Volume. Then follow the steps at How to erase a disk for Mac – Apple Support for erasing.


For information on Catalina's system partitions, see About the read-only system volume in macOS Catalina - Apple Support.


For information on reinstalling macOS from a bootable installer see How to create a bootable installer for macOS – Apple Support


Best of luck!

Jul 20, 2020 6:15 AM in response to dialabrain

Apologies, I noticed after I posted that the original poster was coming from Big Sur beta. When composing the response I thought they were simply trying to reinstall macOS from a bootable installer. I edited the post just before you quoted by the looks of it (nonetheless my post is still incorrect for advising the OP to backup from Time Machine while using Big Sur).


Apologies GourishRC, follow the steps which dialabrain posted, not mine! Let us know how it goes.


Best of luck!

Deleting the Mac-Os Data Partiton

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