How do I downgrade from Big Sur to Catalina?

Hello,

You can download Mac OS Catalina by following the below link... it will take you to the Apple Online App Store. However, you will not be able to downgrade on a Macintosh HD that already has a newer version, such as Big Sur. You will have to erase the Macintosh HD. If you use the Cloud for everything, your Messages, Photos, Mail, Desktop items, Documents will all download to your Mac once the Mac OS downgrade installation is complete. If you store any of your Music, Movies or TV Shows on your Mac, you will need to back them up on an external drive.

https://apps.apple.com/us/app/macos-catalina/id1466841314?mt=12

The provided links below will walk you through a reinstallation... navigate to the lower half of the page to read the section "Other macOS installation options".

How to reinstall macOS

https://suphttps://support.apple.com/en-us/HT211683

How to get old versions of macOS

https://support.apple.com/en-us/HT211683

Best of Luck...

Daniel

I tried this and it worked. There may be a better way but I put this process together myself. You need a bootable disk with an older version. Because higher level OS will not allow you to just run an older MacOS installer.

1) Make a copy of all your important information on an external drive. It is best to use normal drag and drop and not some fancy program. Because drag and drop is going to work while specialized backups are complicated and are not guaranteed to work. I used a decent Samsun external ssd an formatted it using "disk uitily" exactly the same as my mac is. In my case "APFS". DIskutiity is standard on Mac and you will find it from "LaunchPad". Remember it launchpad on Big Sur has a different looking icon but works the same. Please use a good high quality drive it is your data! Then after you copy everything you want go to Finder or DiskUtility and eject it. Disconnect it and keep it some place safe. This will be useful as a last stand backup. Apple Cloud is great and I use it but never hurts to have a simple physical backup in your house.

2) Now you need to make a bootable Mac drive with the version you want downgrade to. You need another external drive. I used another SamSung USB 256 gig SSD. But a smaller pin drive probably works. Then you need to install and older version of MacOS on it. The version you want to downgrade to. You can download it but can be a pain to find. It is much better if you keep around the MacOS installers from older versions on the backup disk for times like this. Once you have a say MacOS Catalina or Mojave installer you need to install it on the external driver [IMPORTANT: Do not use the backup drive! Use another one]. As I said you need a Mac running that or an older version of MacOS. I have 3 Macs and I used one running Catalina to run the installer. Before using the installer you need to format the external drive to a GUID partition using the DiskUtility. NO need to partition or add volumes. Now when you run the MacOS Catalina [on a machine running Catalina or older] you get to pick a disk to install on. Make sure you use the external OS disk you just formatted. It will be a while and now you got a bootable Catalina external USB drive. Be sure to put a copy of the MacOS Catalina installer. Now plug it into your Mac which you want to downgrade and then boot it. Remember you need to switch the boot disk from Startup Disk which is in System Preferences on the machine you want to downgrade.

Two things;

A) Keep it for future possible use.

B) You Mac may not allow booting an external drive. This requires you go to Security Utility and allow it. This utility is only available in the boot/rescue screen not while Mac is booted. You need admin privilege but you can go in and allow booting.

external drive.

3) Now that you got the system booted from the external drive. BE SURE you backed up all you need on both Apple Cloud and a disk at home.

WARNING: this will wipe out your original internal disk and all on it!

Open the DiskUtility and totally erase the original drive. Next make a GUID partition on it.

Run the MacOS Catalina installer while booted from the external disk and install a brand new Catalina on your Mac. Your Mac is now downgraded! Beware you must configure it and either shut off the internet or as soon as you get in go into Updates from System Preferences and shut automatic updates or it will update you right back to Big Sur.

Now restore your old stuff. Apple Cloud is better but I used my hand made backup disk. The benefit was to avoid installing old apps I did not need.

If downgrade is still the case, there are two options to downgrade: you may use Time Machine (with Catalina backup) to go back, and second one is downgrade using bootable OS installer.

Don't forget to backup anyway!

There is also an article with more precise instructions.

This is the link

https://apps.apple.com/us/app/macos-catalina/id1466841314?l=en-us&mt=12

very important steps:

1) Backup all your data.

2) don’t try to install on Big Sur. You need to make a bootable USB stick with Catalina (you can find many way to do so searching the web), and boot your computer with it (press Alt at restart to choose).

3) Your hard drive needs to be erased totally.

4) Install Catalina and restore your data. I had many troubles after it, restoring my Applications was causing a bad restart with my iMac Pro turning off at 75% of progress bar.

Backward migration has never been an easy task, whether it's from Big Sur to Catalina or Catalina to Mohave or any backward migration; once updated to the latest operating system, you can't go back and if you do everything you did while on the latest operating system must be reinstalled manually, (individually folder-by-folder) or it will be lost.

Backward migration has multiple paths;

One method is a complete factory reset and installs the original operating system that came with your computer at purchase (instructions, https://support.apple.com/en-us/HT204904), which you then move up to Catalina and reinstall via apple migration using the last Time Machine backup you did before installing Big Bur.

The second method is to download Catalina and on a separate flash drive or backup disk, create a bootable installer, then erase your hard drive either with Disk utility or starting up from macOS Recovery (instructions, https://support.apple.com/en-us/HT204904).

Good Luck.

You should probably tell Apple how you feel.

https://support.apple.com/en-us/HT211683

It’s pretty simple. Just erase the startup drive and restore from your backup.

The fastest - Via Time Machine Backup via Recovery Mode - Command + r - immediately at restart then attached the TM Drive and when presented >> Restore from Backup.

Ha! I doubt you'll be able to and of course, eventually you'll have to. But I wish too I coudl get rid of this. It makes my Mac look like a PC. The UI is horrible with less contrast between sections and thinner/tinier type everywhere. Jonny Ives is still getting his way apparently, making the Mac (and iOS) a crappier experience with every update.

Well, I spent the last four days trying to downgrade to Catalina and I had very big troubles. I have a baseline, 2018 iMac Pro and the backup of everything. The troubles came after the restore from backup. I restored my user data and applications. All was ok, but only after the first restart: the progress bar, around 75% stopped and the computer was turning off instantly. There was no way to fix it, no NVram zapping, no SMC reset, no Safe Mode booting was working at all. I had to repeat this many times to get it working, after restoring only my home folder and installing back all my apps one by one. Now finally I can use it, though is a long job to have all my apps installed. One thing remains of Big Sur, the startup chime.

Apple is moving to a world game-changer of computer integration by unifying iPhone Processing with apple computers universally using Apple's new processing chips, all controlled by Apple's latest operating system, macOS Big Sur.

It's important to take time to understand these changes and not be left behind this new technological leap.

New features coming with macOS Big Sur.

macOS Big Sur brings a refined new design, powerful controls, and intuitive customization options to the most advanced desktop operating system in the world.

https://www.apple.com/macos/big-sur/features/

Can you stop the sales pitch and answer the question? Many of us feel that Big Sur is not suitable for our needs and we'd like to move back to an OS that works for us. I've upgraded to Big Sur and now I can't open any Microsoft Office docs without buying another subscription - why????

The problem is not Apples macOS Big Sur, the problem is Microsoft has not yet updated its software to work with Apple Silicon M1 Chip, and are asking Microsoft Word users to use Rosetta 2 until this is fixed.

Microsoft 365 and Office 2019 support for Apple Silicon

Office 2019 for Mac Microsoft 365 for Mac

This article was last updated on December 15 at 9:00 AM Pacific Time.

On November 10, 2020, Apple announced the availability of new Mac devices based on a custom architecture known as Apple Silicon. This article outlines the support of Microsoft 365 and Office 2019 on Apple Silicon devices.

hip.

The December 2020 release (build 16.44) provides native support for both Apple Silicon and Intel-based Macs. Word, Excel, PowerPoint, Outlook, and OneNote are supplied as a Universal macOS binary, where the Mac operating system will dynamically load the most optimal app components for your device. This release of Office includes the latest optimizations for macOS Big Sur, which is the first operating system to support Apple Silicon.

Common questions

Do I need to download and install a separate package if I'm using a Mac with an M1 processor?

No. The Office installation and update packages contain the optimized code for both Apple Silicon and Intel-based devices. This is true regardless of whether you obtain Office from the Mac App Store, or office.com - which uses the Microsoft Content Delivery Network (CDN).

Is there any reason to run Office under Rosetta 2 translation?

For the best experience, we recommend that you let the operating system decide how it should load the Office apps. There are a small number of scenarios where you may need to tell macOS to prefer using Rosetta 2:

• You use Excel's Get and Transform functionality (also known as Power Query)
• Your app workflows rely on a third-party plug-in that has not been updated to include native support for Apple Silicon
• 
  

For instructions on how to use Office apps with Rosetta 2, see Use Office for Mac with Rosetta and Apple silicon. In the case of a third-party plug-in, contact your vendor to see if they have an update available.

Big Sur is a big mess and a big fail!

My sister downloaded it and her late 2015 iMac became useless. I tried to reinstall it and it hung up at the dreaded

"Less than one minute remaining"

Now I have to do a clean erase and load Catalina.

Reminds me of all the bad OS from Microsoft in the early days.

Apple needs to apologize to its customers who rely on their computers to make a living and have lost productive time and money.

It is not acceptable any longer as the infant days of computing ended a long time ago.

This reads like an excuse. Apple used to be the computer that was easiest to use. Reading all of these complaints -- looking for one that is my problem -- is so discouraging. Get it together, Apple. Don't give us excuses. Fix the problems. This is supposed to be the company making insanely great products, not insanely frustrating ones.

I don't like Big Sur either, but I don't care to go through the mess of reverting back to Catalina. It's mostly stable enough for me to use it, and my concerns are more with the design changes that don't seem to make my eyes happy. I have managed to tweak the UI through Accessibility options like reducing transparency which does help. But all this White on gray stuff isn't my ideal of progress.