Why did a failed Catalina install, and restore to Mojave, yield a new disk volume Macintosh HD - Data

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Why did a failed Catalina install, and restore to Mojave, yield a new disk volume Macintosh HD - Data

Why did a failed Catalina install, and restore to Mojave, yield a second, new disk volume Macintosh HD - Data?

The Catalina upgrade failed because of "an "opt" file couldn't be saved in Macinotsh HD." I tried three times and gave up.

I Restored to Mojave and now have a second disk volume, Macintosh HD - Data. Looking inside each of HD or HD -Data I can't tell which has Mojave in it. The HD volume has lots of grayed-out files.

But never mind; how do I cleanup this mess? Once I do that I'll deal with the "opt" file, which is invisible in the Finder but seen on "Search."

Thank you.

MacBook Pro 13″, OS X 10.11

Posted on Jul 18, 2020 9:10 AM

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Answer 1

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Barney-15E

Level 10

112,998 points

Jul 18, 2020 9:26 AM in response to Bruce L.

Catalina splits the drive into two volumes, one for the OS and one for your data.

Which drive did you select to install Mojave onto? If you chose Macintosh HD, then that is where Mojave is installed and you can remove the - Data volume.

If you chose the - Data volume, then you can remove the other volume.

If you are not concerned about what is on the drive, use Recovery to remove both, then create a new Macintosh HD volume and reinstall on that.

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Answer 2

Bruce L. Author

Level 1

28 points

Jul 18, 2020 10:47 AM in response to Barney-15E

I don't recall Recovery offering a choice of drives.

In the Finder, HD - Data has numerous items incudinging folders stamped with the time of the restore to Mojave yesterday.

The HD in Finder has a few items dating from a month or so back. But it includes a System folder and the "opt" culprit, and an Applications folder with a lot of apps in gray.

So I assume, HD - Data is the crucial volume and I can remove HD. How do I remove HD? Should, I rename HD - Data; HD (how)?

If this is successful, should I try to install Catalina again. Is that wise?

Thank you

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Answer 3

Barney-15E

Level 10

112,998 points

Jul 18, 2020 4:37 PM in response to Bruce L.

You should be able to remove it in Disk Utility.

You should see Macintosh HD - Data listed at the top if it is the Startup drive.

If so, select Macintosh HD in the disk list and click the Remove Volume button.

If it won’t let you, boot into Recovery and see if you can remove it in Disk Utility there.

You can rename the drive in the Finder

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Why did a failed Catalina install, and restore to Mojave, yield a new disk volume Macintosh HD - Data

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