Can't downgrade 16" MBP from Monterey to Catalina with Carbon Copy Cloner due to bad Bombich instructions, help!

[tomekinc]

Hey folks, been trying since yesterday to downgrade 16" MBP 2019 Monterey to Catalina. I have a Carbon Copy Cloner (been using for years) but first time I have to downgrade. Bombich provided me incomplete instructions before they left for the weekend, and I'm was hoping this was a 1 hour process, (it's been 10). I have a Bootable External Backup, there's no issue with it, the issue are the instructions.

Step 5 is missing parts, and then at Step 7, although you can select the disks, and even click the eject button literally nothing happens. I have spent hours searching every tech forum and FAQ, Youtube, nothing. Nothing explains or shows step by step how this is done. Apple Support claims you cannot erase a SSD.

All the way at bottom: https://support.apple.com/guide/dis...at-a-storage-device-dskutl14079/21.0/mac/12.0

This link is Bombich FAQ, go to Downgrade BOOTABLE disk, that is what I have: https://bombich.com/kb/ccc6/best-practices-updating-your-macs-os

This picture shows where step 7 stops. You select a scheme and press erase to nothing. No scheme matters, and it doesn't matter with parent you select on the left (parent meaning the top two in the Internal).

So how do you use CCC to downgrade from Monterey to Catalina? I don't have Time Machine, and I don't have any other backups other then this one Catalina on my external CCC bootable SSD.

Has anyone every accomplished such a task?

https://imgur.com/a/T2yXd2W

 

[kitKAC]

Under Container disk1 on the left, select each volume and delete it using the - button, you should hopefully be able to Erase the disk again.

 

[tomekinc]

Under Container disk1 on the left, select each volume and delete it using the - button, you should hopefully be able to Erase the disk again.

But you can't, that's where I need help. That is exactly the problem I'm explaining that your procedure does not work at all. The picture I show, it doesn't matter what you select on the left, you select the options as I show in the pic and there is a blue erase button and that does nothing. You can click it, but it does nothing. Rebooting and restarting, unplugging changing ports etc does nothing. Choose any container or anything on the left and it simply does not matter, the blue erase button presses down but does nothing.

According to the Apple link I provided the note at the bottom says you can't erase a SSD.

Is this what is happening here?

 

[kitKAC]

I’m saying to try and delete the existing volumes first, then you can do an Erase on the container to create a new volume.

Of course you can erase an SSD, I literally did it with my own Mac an hour ago.

 

[tomekinc]

I’m saying to try and delete the existing volumes first, then you can do an Erase on the container to create a new volume.

Of course you can erase an SSD, I literally did it with my own Mac an hour ago.

But HOW? There is no separate Delete function. You have only one Erase button. And you cannot erase anything.

I don't understand you steps because this is literally the problem I'm having. I cannot erase it, no matter what I select or do, it makes no sense when you say to delete it before you erase it. There's just one erase option and that's it. And it simply does not work at all.

 

[tomekinc]

I'm attaching two pictures, the first shows the step where you select the container on the left, first you're suppose to unmount the Upgrade thing as it's the ONLY thing that can be unmounted so per the instruction I unmount it. Then I select the container and press Erase at the top gray button.

Next picture opens up the next window, and see that Erase button on the bottom right? Pressing it does NOTHING. This is where the instructions fall apart. No matter what I select in scheme or options, literally no option selected will allow for Erase.

You can press that button all you want but nothing happens. Not another pop up, no system resources go off, nothing. Nothing happens.

Not only that, but I accidentally Erased the Update thing and for some reason it reacreated itself, Now when my Monterey OS boots it goes through TWO boot sequences.

 

[gilby101]

The instructions you are following, say (steps 7 and 8): select the whole disk device (i.e. Apple SSD...) and then erase. That is not what is in your first screenshot.

 

[tomekinc]

The instructions you are following, say (steps 7 and 8): select the whole disk device (i.e. Apple SSD...) and then erase. That is not what is in your first screenshot.

Hi, I'm explaining that is exactly what I have done. I have selecting every sinlge thing in that left pane and none will delete.

The pictures are exactly what you are saying! This pics literally are of me trying to delete Apple SSD on the left! I don't understand why you are saying I am not doing that! That is literally the entire problem I select the Apple SSD on the left, and then the next picture is that popup with the Erase button on bottom right. That is what happens when you select Apple SSD, that other window pops up.

So what do now?

 

[gilby101]

1) I don't have a Mac with a T2 chip, but what are your T2 security settings? https://support.apple.com/en-au/guide/security/secc7b34e5b5/web

2) Bootable clones are dodgy things, and no longer fully supported by CCC. You might be better to do a clean install (either Internet Recovery or bootable Catalina installer) and then use Migration Assistant to restore your apps, settings and data from your CCC backup.

 

[gilby101]

3) Boot into Recovery Mode to erase the internal SSD. https://support.apple.com/en-au/guide/disk-utility/dskutl14079/21.0/mac/12.0

Try this first.

Sorry you have already read that Apple link (but not followed it).

 

[kitKAC]

But HOW? There is no separate Delete function. You have only one Erase button. And you cannot erase anything.

I don't understand you steps because this is literally the problem I'm having. I cannot erase it, no matter what I select or do, it makes no sense when you say to delete it before you erase it. There's just one erase option and that's it. And it simply does not work at all.

In the toolbar, towards the left side are two buttons labelled Volume + and -, select each volume and press - to remove it.

If that doesn't work, boot into the Recovery Volume for the OS that's currently installed and you should be able to erase the disk from there. Older versions of Disk Utility can have issues wiping APFS containers made with newer macOS's.

 

[gilby101]

Apple Support claims you cannot erase a SSD

The Apple Support document you quoted says that (in some circumstances) you can't do a secure erase of an SSD. That is because when preparing a boot disk (to reinstall macOS) you should do a standard erase, install macOS and use FileVault to encrypt after everything is running.

 

[gilby101]

If that doesn't work, boot into the Recovery Volume for the OS that's currently installed and you should be able to erase the disk from there.

Good, that's two of us saying that - must be right!

 

[tomekinc]

@gilby101 - appreciate all the things, There's a much much easier way then using Migration Assistant. I don't have corruption issues, MA is for when I'm really having problems. I simply have incomplete instructions, I literally need one person whose done a downgrade with CCC6 to chime in.

@kitKAC

I made a video, here is exactly what is happening. You can see that the - is greyed out. Recovery Mode, I'm not familiar with how to use CCC in this situation and I don't want to risk it, my disk is not corrupted I'm not having that kind of an issue. It's got to be bad instructions from Bombich.

(I don't know why youtube uploaded this at only 240p...)

 

[gilby101]

It's got to be bad instructions from Bombich.

Let's say incomplete. Bombich's instructions are somewhat generic and may not apply precisely in all situations. In your case:

a) Make sure you can boot from the CCC backup. (steps 1 to 3). You have already done this.
b) Boot into Recovery Mode and then follow steps 4 to 8. Try it!!!
c) Boot to your CCC backup and follow steps 9.....

 

[tomekinc]

I have tried booting into recovery mode, but there is no way to also have the backup booted up and do the instructions as above. What I'm saying is there's a whole bunch of other things happening I do not understand.

But what would be a better approach is again, why aren't the steps in the video working? What is it about my steps that the erase button doesn't work? I don't want to try Recovery, that's too harsh, we need to finish with the video. Literally everyone says just click erase, ok, hers's the video...now what?

 

[arw]

But what would be a better approach is again, why aren't the steps in the video working? What is it about my steps that the erase button doesn't work? I don't want to try Recovery, that's too harsh, we need to finish with the video. Literally everyone says just click erase, ok, hers's the video...now what?

Something like this can happen when changes on the SSD have been made with a newer version of disk utility.
What I did was to create a bootable USB installer from the latest Monterey and boot from that. There disk utility could erase the SSD.
You are using the existing recovery partition of your Mac, not internet recovery?
Internet recovery should also provide the latest version of disk utility.
Boot from internet recovery (cmd+opt+R) and try deleting or first repairing the SSD/container/volumes again:

Use macOS Recovery on an Intel-based Mac

Learn how to use macOS Recovery on an Intel-based Mac.

support.apple.com

The next step I would try is deleting the disk from Terminal with diskutil.

 

[tomekinc]

You are using the existing recovery partition of your Mac, not internet recovery?

Sorry, can you elaborate, I don't get what this mean?

I also don't know if with your steps how I install or bootup with Catalina from my CCC 6 Backup.

 

[arw]

Sorry, can you elaborate, I don't get what this mean?

I also don't know if with your steps how I install or bootup with Catalina from my CCC 6 Backup.

When you boot with (cmd+R), the local recovery partition is used (which apparently doesn't work to erase the SSD).
With (cmd+opt+R) a fresh and independent temporary recovery volume is created from scratch from the internet.
If you manage to erase your SSD this way, you can continue as planned: Boot from your external backup, format the internal SSD and clone your external backup to the internal SSD.

 

[tomekinc]

When you boot with (cmd+R), the local recovery partition is used (which apparently doesn't work to erase the SSD).
With (cmd+opt+R) a fresh and independent temporary recovery volume is created from scratch from the internet.
If you manage to erase your SSD this way, you can continue as planned: Boot from your external backup, format the internal SSD and clone your external backup to the internal SSD.

I accidentally created a second one, under Internal, where it says, UPDATE (you can see in the video), there are now two because I erased one and somehow the system recreated itself. So now when Monterey boots it goes through two boot sequences. So I don't want to delete that again, and have three.

 

[gilby101]

Without a hand hold

I though I was. Telling you to do steps as Bombich outlines, but to do steps 4 to 8 in Recovery (or Internet Recovery) mode.

Failing that you need to find Mac support specialist near you and get them to recover your system.

 

[arw]

but to do steps 4 to 8 in Recovery (or Internet Recovery) mode

This. Then report back.

 

[tomekinc]

I though I was. Telling you to do steps as Bombich outlines, but to do steps 4 to 8 in Recovery (or Internet Recovery) mode.

Failing that you need to find Mac support specialist near you and get them to recover your system.

Ok, I've now bricked the laptop and am operating off the bootable CCC backup.

I erased the volume with Command + R, and then get out of Disk Utility and follow CCC instructions booting up in command c, and here are the results. wtf what does this even mean?

 

[arw]

I erased the volume with Command + R, and then get out of Disk Utility and follow CCC instructions booting up in command c, and here are the results. wtf what does this even mean?

From your working backup, can you post a screenshot of Disk Utility showing the internal SSD
or open Terminal (Applications > Utilities) and type

diskutil list

Press Enter and post the result.

edit: Is FileVault really enabled on your bootable backup? This is what the other screenshots indicate.
If so, follow the steps you posted.

Don't worry, nothing is bricked.

 

[tomekinc]

Did you completely erase all volumes of the internal SSD?
From your working backup, either post a screenshot of Disk Utility showing the internal SSD
or open Terminal (Applications > Utilities) and type

diskutil list

Press Enter and post the result.

edit: Is FileVault really enabled on your bootable backup? This is what the other screenshots indicate.
If so, follow the steps you posted.

Brah... I thought you were holding my hand. Yes, File Vault is turned on, it's a security feature, how would I know to turn it off?

I deleted the the APPLE SSD AP1024N Media, at the Cmd + R Disk Utility Screen, then rebooted into the CCC backup, opened CCC and then the above happened.