This volume is not formatted as APFS

Well, I finally got to my goal: upgrading Mojave running on Mac OS Extended (journaled) to Catalina running on APFS.

1. I found some advice suggesting that the FS conversion could be done in place: https://www.macobserver.com/tips/how-to/upgrade-mac-apfs-after-high-sierra/ When I tried it, the option in Disk Utility was grayed out (and I did select the proper boot volume).
2. I reformatted my internal SSD to APFS using Disk Utility.
3. Using Disk Utility, I attempted to restore the backup image I made using SuperDuper to the newly-formatted internal APFS SSD. Disk Utility errored out, saying that the volume in the image (which was not APFS) could not be restored to an APFS volume.
4. I used SuperDuper to successfully restore my backup to the internal SSD APFS volume.
5. I then upgraded from Mojave to Catalina using Software Update, with no problems.

You may be able to boot into Recovery Mode and convert the volume to APFS.

https://www.macworld.com/article/3230150/macos-high-sierra-startup-ssd-volume-must-be-apfs-other-drives-can-wait.html

You should make sure to have good verified working backups before attempting the procedure. If something goes wrong you will most likely need to erase the drive and either perform a clean reinstall of macOS or a restore from a backup.

See if you can convert the file system to APFS on the fly.

https://discussions.apple.com/thread/250713725?answerId=251390345022#251390345022

You should definitely make sure you have good verified working backups first in case something goes wrong. Also make sure you can either boot into Internet Recovery Mode (Command + Option + R) or boot a macOS USB installer in case you can no longer boot to the internal drive.

Clone your Mojave to an external drive. Reformat your internal as a APFS drive, something that should have happened when you first installed Mojave. Then you can boot from your clone and clone it back to your internal drive. Then boot Mojave from your internal and upgrade to Catalina.

After speaking with Apple, I attempted to erase the drive from Restore (shut down then command+R upon restart) so I could then restore the data from Time Machine backup. BUT, when I got to the formatting options, there was no APFS option visible via disk utility. You might see the APFS formatting option on your Mac and so you can ignore the rest of this saga.

What I then did was reinstall (from recovery mode) the OS. For my Mac it was Sierra. Once I had a clean install of Sierra I went to Software Update to get a copy of Mojave. I downloaded it and installed - checking to make sure this time Mojave had converted to APFS (It had ). Then I returned to Software Update and downloaded Catalina. Once I tried to install was given a new error that the download was corrupted.

Lastly I went to the Apple site and downloaded Catalina directly. Finally it installed correctly.

Yes, it was a complete clusterf**k. But those are the hoops.

I encountered this issue on my mid-2014 MBP Retina 15". Over the years, I've upgraded through each OS sequentially, including Mojave.

However, I know exactly how I got to this point. About a week ago, I replaced a failing SSD (wear leveling had reached its limit). Before restoring, I formatted the new SSD as Mac OS Extended (Journaled), not realizing that Mojave was using a new FS.

So, apparently, I face the prospect of reformatting/restoring once again, which is somewhat of a PITA, plus which the restore took half a day because I was restoring from a backup image on my home network's NAS. I'll do that if I have to, if there's no workaround...?

Apple *should* fix this problem, since they allowed it to occur. The problem evidently arose from the initial beta upgrade to High Sierra (or Mojave?) which required the user to manually select an upgrade to the APFS format. I, and apparently many other users, did not do this; I did not understand the ramifications of this at the time. Now we are stuck with Mojave (10.14.3) that cannot be further upgraded without completely erasing and reformatting the drive and copying it back from a backup. Even Disk Utility from Recovery Mode does not allow an upgrade to the APFS format (it is greyed out).

Call me an idiot for getting into this mess -- but Apple should have made this idiot proof!

Just so you know, there seem to be a number of us that upgraded to Mojave by the software update process and the software didn't update to APFS. That's not our fault. That is a glitch by Apple.

Mojave drives are supposed to be APFS, so Catalina is expecting it to be APFS.

I know through testing that it is possible to clone a Mojave partition on top of a HFS+ partition. Perhaps you may have previously done that.

Well, Randy_N, at least I can tell you what NOT to do. I'm just finishing restoring my MacBook from a backup (I use TimeMachine with WDMyCloud) because I followed what was meant to be "a safe option" to convert into APFS. I run my computer in Recovery Mode, unmounted primary drive, converted the filesystem into APFS and it worked. The filesystem is now APFS but I had to either reinstall the system or restore it from backup, which I did. After almost 4h my computer will be like new :)

Apple can't fix how you wound up with Mojave on a HFS+ partition, since the normal installation of Mojave automatically changes HFS+ to APFS.

Hi,

I had success by calling Apple Support and they walked me through the back-up and reformatting. Took about 15 minutes and that took care of the issue. Another great job by Apple Support!

True. I've got 2 identical MacBooks Pro, both with MacOS Mojave, one has APFS, the other one Mac OS Extended (Journaled) file system...

If I wanted compatibility problems, system crashes and other impediments, I would use Windows :)

Please Apple, come up with a solution to this issue, as I don't want to get back to "know all about computers and software" state. For many years I've been comfortable with "it's so easy, I don't have to do anything" state and I'd like to keep it that way.

Why do you think this sneer is necessary to find a solution? I seem to have the same problem yet I always ran the upgrades the way apple provided them. I am running Mojave 10.14.4 at the moment and if you were right I should not have this problem. On top of that if automatic conversion was possible in Mojave, why not do it in Catalina as well?

I have the same problem. Mojave has worked fine but can't install Catalina. Think I'll skip it for the time being unless someone has a solution