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.

User profile for user: chicostrat
chicostrat Author
User level: Level 1
5 points

Mojave with Macintosh HD - Data partition

Hi, my wife's MacBook Air 2017 Mojave has a mysteriously filled up hard drive. A large portion of the HD is taken up by additional, unmounted partitions though the main suspect is the "HD - Data" partition.


I vaguely recall how it got there. I tried upgrading her laptop to Catalina and it locking up during install. Since she had a time machine backup, I wiped the drive and re-installed Mojave and didn't give it much thought again. But she's be complaining about poor performance for the many months since and I now realize that the botched upgrade must have created an additional partition.


I'd like to know if I can safely delete that partition or if there's some reason why I should keep it.




MacBook Air

Posted on Dec 17, 2020 10:28 PM

Reply
Question marked as Top-ranking reply
User profile for user: Eau Rouge
Eau Rouge
User level: Level 8
42,602 points

Posted on Dec 17, 2020 11:06 PM

When Catalina is installed it creates two Volumes, Macintosh HD

and Macintosh HD Data.


When you went to erase the Disk you did not do it properly

you just erased Macintosh HD and left Macintosh HD Data.


When you erase a Disk open Disk Utility, click View in the

menubar and select Show All Devices.

Your screenshot shows you have already done that.

Then highlight the Disk not the indented Volumes

The Disk in your case is Apple SSD AP0256J Media

click Erase

give the Disk a name

Format: APFS

Scheme: GUID Partition Map

Click Erase

When done quit Disk Utility


Now you can install Mojave again

and once that is done you can restore

only the personal data from the backup you made earlier.

View in context

Similar questions

3 replies
Question marked as Top-ranking reply
User profile for user: Eau Rouge
Eau Rouge
User level: Level 8
42,602 points

Dec 17, 2020 11:06 PM in response to chicostrat

When Catalina is installed it creates two Volumes, Macintosh HD

and Macintosh HD Data.


When you went to erase the Disk you did not do it properly

you just erased Macintosh HD and left Macintosh HD Data.


When you erase a Disk open Disk Utility, click View in the

menubar and select Show All Devices.

Your screenshot shows you have already done that.

Then highlight the Disk not the indented Volumes

The Disk in your case is Apple SSD AP0256J Media

click Erase

give the Disk a name

Format: APFS

Scheme: GUID Partition Map

Click Erase

When done quit Disk Utility


Now you can install Mojave again

and once that is done you can restore

only the personal data from the backup you made earlier.

Reply

Mojave with Macintosh HD - Data partition

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