Desperately need to remove Catalina and reinstall Mojave

So, I tried yesterday but I was faced with slightly different options and I didn't feel like testing my luck (or capabilities in this case).

In my Utility Disk I cannot change the Macintosh HD and Macintosh HD Data's format to Mac OS Extended Journal. However, I could do it with the "container disk" they're both in. This container disk is itself inside the Fusion Drive.

At this point I'm unsure about which one I should erase and rename. And if I erase the "Container disk", should I rename it as "Macintosh HD" or keep "container disk"?

Apologies, I'm terrified I'm going to make a fatal mistake..

First off you don’t need to worry as you have a TM you will always have your data in some form. If you use iCloud Drive when setting the Mac back up it will sync with all your files anyway. In regards to the disk utility are you doing this in recovery mode.

Thank you @Scily98, YOU'RE A LIFE SAVER!

I have a rMBP mid-2014, that was running on Yosemite and did the mistake of upgrading to Catalina. Immediately noticed significant battery drain and wanted to restore my previous OS. Like all of us here, I got the same error message.

I followed your procedure, but was unable to raise the volume after deleting Macintosh HD and Macintosh HD-data. I tried to erase the volume to choose the OS extended (journaled) format but gave me an error saying that could not be done as HDD was in use. Tried to unmount it and remount it, but all in vain. With my data deleted, I then just tried to do the restore of my TM backup and IT WORKED.

Decided to upgrade to El Capitan for now as I was having some issues with apps no longer supporting Yosemite, the culprit of this whole mess. Seems to be doing well now, might try upgrading to Sierra or High Sierra eventually.

Thanks again :D

I use high Sierra and have not encountered any issues bar one which is a not that common error with file vault. When I turned it on it caused a whole load of issues which caused some loos of data but apart from that it’s a good OS.

Had this exact issue yesterday, and you saved my laptop!! Thank you so much!! We are back to El Capitan, I couldn't be more happy. A hundred times thank you! Advice for those of you who want to try this, it works, however you need a backup on Time Machine.

I’m glad it worked for you. Just as a side note you can restore the majority of your data without a time machine from the operating system you wish to restore too. It would involve doing a time machine of the most recent Mac system then using migration assistant at a later date. Just a FYI for anyone in the future.

I tried these steps, and my Mac completely useless. It failed to boot.

I was desperate with catalina flaws then I seek for help to get back using my TM. Then I found this discussion. I'm sure I have follow all the step given, then my mac successful back to El Capitan. But after I restart my mac, the bar loads until 3/4 then it fade out, blink again at the apple and 3/4 bars and then fade out again and again, and again.

Please, I have followed your steps, then you have to help me to solve this 🙏

My initial reply to this thread was deleted/censored by Apple today.

Censorship = trust issues because what other issues are Mac hiding from their (once) loyal users??? I've been a Mac user for 13 years.

I hope you solved your problem. Apple Support's fix for my computer has left it glitchy and now even locks me out of my Time Machine backup as well as my main external hard drive. I will be calling them until they fix my computer the way it was - not the way Mac wants it to be.

My Mac mini functioned perfectly prior to (or or about) 15 July 2015 when Security Update 2020-004 tried to install itself on my Mac but ended up causing my mini to enter an infinite loop every time I started it up.

Computer problems caused by Mac's/Apple's own software are problems that Mac/Apple should address and should make their users aware of - not hide them by deleting comments: because this action looks and feels like 'cover up', not transparency and 'we want our users to have the best experience'.

There are significant problems now - who knows how many users' problems Mac are truly hiding? Trust has evaporated.

I expect this comment to be deleted by Apple too.

I have the same problem and can't restore from either Time Machine backup from either external disc or Time capsule....

My Disk utility has the "Macintosh-HD - Data" option but I cannot delete or erase this.

most of my application doesn't support MacOS Catalina, want to revert back to Mojave

In my case there was a partition install on the hard disk which I could be boot from, still lost months of e-mails and data.

let me try this

DUDE PLEASE! For the love of God i have messed up. I’ve deleted my macintosh data and now the only option I have is to restore it as APFS PLEASE HELP MAN. I WISH I NEVER UPGRADED TO FXCKIN CATALINA

How and what do you mean by deleting Mac data. I’m sure we can get something back.