This volume is not formatted as APFS

My first attempt: backup, cmd-R recovery, re-partition/format to APFS, restore from backup with recovery mode, didn't work since the recovery mode restore formats that drive back to the incorrect partition type.

This worked:

• Full backup with Time Machine
• Reboot with cmd-R and formatted with Disk Utility to APFS (complete wipe)
• Installed Mojave while using recovery mode tool
• Booted to default "blank" Mojave
• Migrated everything from backup to Mojave with Migration Assistant.
• Installed Catalina update.

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.

When Mojave was installed it would have automatically updated your boot drive to APFS unless you told it not to. However, you should be able to convert your boot volume to APFS without destroying your data. Launch Disk Utility, select the volume (not the drive itself), then right-click and select Convert to APFS.

Be sure to back up your boot volume before doing anything in case something goes wrong.

After a several hours of trial and error, and piecing together everyone's suggestion, here's what worked for me without having to reformat/erase drive.

My setup:

• iMac with Internal Samsung SSD (named My SSD)
• Mojave OS
• Format: Mac OS Extended (Journaled)
• Scheme: GUID Partition Map

1. Downloaded Catalina
2. Restart in Internet Recovery Mode (Command+Option+R after restart)
3. macOS Utilities -> Disk Utility
4. Select "My SSD" volume and Unmount
5. Edit -> Convert to APFS
6. Quit Disk Utility
7. macOS Utilities -> Reinstall macOS
8. Install macOS Catalina

Hope that helps.

@jayhawkfan88's solution worked for me, however there was one extra step that took me a bit to figure out (see step 4/5 below).

Note: I no longer have the original on board Drive, I upgraded it about a year ago to a 500GB SSD, which is how I am guessing I got into this predicament. This solution still worked for me even though I have a non OEM Drive.

Edit of jayhawkfan88's solution that worked for me below:

1. Downloaded Catalina
2. Restart in Internet Recovery Mode (Command+Option+R after restart)
3. macOS Utilities -> Disk Utility
4. Select "My SSD" volume and Unmount (My drive was already unmounted, and the Convert to APFS in step 6 was greyed out).
5. If your drive is already unmounted and you cannot select Convert to APFS in step 6, mount the drive first, you will be asked for your password to unlock the drive. Then unmount it. The Convert to APFS option will then be available (after the drive has been unlocked and unmounted).
6. Edit -> Convert to APFS
7. Quit Disk Utility
8. macOS Utilities -> Reinstall macOS
9. Install macOS Catalina

I don't think there is a quick solution. How I did it after trying all proposed ' fixes':

1. Made a full backup with rsync
2. Reboot with cmd-R and formatted my drive with the Disk Utility to APFS (complete wipe)
3. Installed macOS (Mojave) and booted normally
4. Restored everything with rsync
5. Upgraded to Catalina...

Downside of this method ...It took a few hours. But other than that it went flawlessly and everything works smoothly.

I did something similar:

• Full backup with Time Machine to external SSD
• Reboot with cmd-R and formatted with Disk Utility to APFS (complete wipe)
• Installed Mojave while using recovery mode tool
• Booted to default Mojave
• Migrated everything from backup to Mojave with Migration Assistant.
• Installed Catalina update.

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.

yeah... none of the proposed solutions worked, Apple is not giving any response so I bit the bullet and made a full backup with rsync, rebooter with cmd-R formatted my drive with the Disk Utility to APFS installed macOS (Mojave) and booted normally restored everything with rsync again and upgraded afterwards to Catalina...

...aaand discovered I couldn't connect to my NAS anymore. Probably due to the removal of smb v1.0 support, fixed it for now by putting a raspberry pi between the nas and Mac but ~sighs~ this is not the "it just works" Apple as it always has been.

And frankly after a few hours... I'm rather underwhelmed by Catalina

bj3john4 wrote:

HWTech wrote:

Did you try erasing the whole physical drive? In order to see the physical drive in Disk Utility you need to click on "View" and select "Show all devices". You should then be able to select the physical drive in the left pane of Disk Utility to erase the drive as GUID partition and APFS (top option).

Yes, it was still "greyed out". But the Samsung SSD is currently installed as my internal drive. Would this make a difference?

Is this a traditional 2.5" SATA SSD?

HWTech wrote:

Maybe your system firmware was never fully updated so macOS is blocking you from using APFS.

I'm not sure I follow... firmware to the Samsung SSD?

Your comments have been helpful... thank you!

I mean the computer's firmware. Recent versions of macOS are supposed to install new firmware onto the computer as part of the upgrade process, but sometimes this process is skipped. Without the updated firmware the computer may not be able to use APFS on the boot drive. Unfortunately Apple no longer lists the most recent firmware revisions for each product.

What is the exact model of your computer? You can get this information by entering your serial number here or here.

If you need to convert to APFS run your Mac in recovery mode and use disk utility to convert your drive. In disk utility unmount drive first and then convert option becomes available.

On my MacBook Pro 15-inch 2016 I had Mojave and Disk Utility did not offer me an APFS transition option at all. I searched in recovery mode.

First I had to install Catalina on an external SSD, so the internal disk became a data one. Then I had to restart my computer from the external SSD to recovery mode. In this version of the Disk Utility, the option to convert to APFS will already appear and you can perform the conversion after unmounting the internal disk. However, after it is not possible to return this internal disk as a bootable disk after converting to APFS. Disk Utility reports an system error. However, it is possible to install Catalina on this internal disk. After installation and restart (it takes about 1 hour), the computer has already started from the internal disk. All my data remains and I have upgraded! Glory! I'm happy :-)

Nevertheless I would expect an easier way to upgrade to a newer version of the system. Apple experts did not invent this so well. I regret all ordinary users who are not as proficient at using computers as Apple programmers ...