From Jun 2020 to Aug 2020, Apple has released several beta versions for macOS 11 Big Sur, both developers and testers can install and run it on a supported Mac. You may be one of them, starting to use this new macOS but unfortunately run into some issues and want to revert to previous Catalina or Mojave version.
No worries, here we will list the easy steps to downgrade macOS Big Sur to Catalina without losing data.
- Why We Need to Downgrade Big Sur to Catalina?
- How to Downgrade Big Sur to Catalina without Losing Data?
- What If Data Lost/Deleted after macOS Big Sur Downgrade?
Recover Data After Mac Downgrade
- Recover files lost due to macOS update, downgrade, crash, etc.
- Recover lost, deleted, formatted data
- Repair corrupted video files
- Use both quick and deep scan modes
- Recover files from internal and external hard drive (USB, SD Card, Media Player)
- Support file recovery on 200+ formats: video, audio, photo, docs, etc.
- Preview files before recovery
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Why We Need to Downgrade Big Sur to Catalina?
MacOS 11 Big Sur is absolutely the biggest update these years since it has moved from 10 to 11, you can find a bunch of update as following in Big Sur:
- New design
- Intuitively customized Safari browser
- Updated Messages app (better control of conversation)
- Redesigned Maps for better and easier navigation
- Improved transparency for Mac App Store downloads
- Expanded photo editing features
- Faster updates to the latest version
……
All the revealed new updates added to macOS11 Big Sur stimulate mac users to upgrade and take the first bite on this macOS version. But later, there occurs problems and some of them want to revert to the previous Catalina version for one or another reasons:
- The Beta version is not perfect, you want to download the official version later;
- It takes longer time to get used to the new version and you don’t want to waste time;
- MacOS 11 Big Sur keeps causing problems;
- Your hardware is not highly compatible on this new version (compromised audio, video or image quality);
- Your favorite app doesn’t work on the new version;
……
No matter what your reason is to revert to an older version, you can refer to following part to downgrade from Big Sur to Catalina without losing data.
How to Downgrade Big Sur to Catalina without Losing Data?
To downgrade Big Sur to Catalina without losing data, here are 6 steps to follow. Before the downgrade, your data matters the most, so don’t forget to back them up though it takes time to finish a backup.
Step 1. Prepare your Mac for downgrade
You should quit running programs and leave enough space (15GB to 20GB) to install Catalina after erasing Big Sur from your Mac hard drive. Also, make sure your mac is connected to the internet for later macOS installer download.
Step 2. Backup files (Important and Required)
It is safe to upgrade or downgrade a macOS version, there is no harm done to your files or data, but data loss after mac update or reversion happens sometimes. If you don’t want to render your data under any potential risks, you are highly recommended to back up files.
There are 2 ways to back up file, either back up your files to an external hard drive with Time Machine or upload your data to cloud-based service for storing, like iCloud, DropBox, OneDrive. But here Time Machine backup is recommended.
- Connect an external hard drive for backup to your mac;
- Run Time Machine and set it up for backup;
- Click on the Time Machine icon in menu bar, choose Back up Now;
- Wait for the backup to finish.
Step 3. Erase macOS 11 Big Sur from your Mac
- Click Apple icon and go to Restart;
- Hold down Command+R when rebooting to reboot your mac in Recovery Mode;
- In the pop-up interface, choose Disk Utility>Continue;
- Then select your Startup Disk, click on Erase tab;
- Choose APFS or macOS Extended format and confirm to Erase.
.png "Easy Steps to Downgrade Big Sur to Catalina without Losing Data (4)")
Step 4. Install macOS Catalina or Mojave
There are 3 methods to install older macOS version on your mac.
Method 1. Download from Mac App Store and Install
- Launch Mac App Store;
- Search macOS Catalina or Mojave, click Download;
- When the download finishes, follow the on-screen instructions to install macOS Catalina or Mojave;
Method 2. Reinstall macOS Catalina or Mojave from Internet
- Click on Apple logo>Restart;
- Hold down Command+R when rebooting your mac;
- In the pop-op macOS Utilities interface, choose Reinstall macOS>Continue;
- Agree to the terms and follow the instructions to download and install.
Method 3. Reinstall macOS Catalina or Mojave from Bootable Drive
- Create a bootable drive of macOS Catalina or Mojave
- Connect the bootable drive to your mac;
- Click on Apple logo>Restart;
- Hold down Option when rebooting your mac;
- Choose the bootable drive with macOS Catalina or Mojave installer;
- Click on Continue, agree to the terms and install a previous macOS version onto your mac.
Step 5. Restore Backup with Time Machine
The only change you want for the downgrade is turning back to a previous macOS version, but you want the files and settings the same as before. In this case, you should restore both your files and settings from a Time Machine backup.
- Click on Apple Logo>Restart;
- Hold down Command+R during mac rebooting;
- Choose Restore from Time Machine Backup from the macOS Utilities interface and click on Continue button.
- Choose the Time Machine backup disk>Continue;
- Select the latest backup, click Restore>Continue.
Step 6. Check if everything is back now!
Now, run your apps on macOS Catalina and check if everything goes well.
If the downgrade still causes problems, restart your mac or reinstall Catalina/Mojave to fix it.
What If Data Lost/Deleted after macOS Big Sur Downgrade?
But what if we still got data lost or deleted after macOS Big Sur downgrade to Catalina or Mojave? You can recover them back with Time Machine backup by following the tutorial in above Step 5. If this still cannot get back your files, you need a professional data recovery program---Cisdem Data Recovery.
Cisdem Data Recovery is a program to recover lost, missing, deleted, formatted files from both internal and external hard drive on mac. It applies to data loss due to system crash, update or downgrade, also supports file systems like APFS, HFS+, FAT16, FAT32, exFAT, NTFS, etc.
Main Features of Cisdem Data Recovery
- Recover lost, deleted, formatted data
- Recover files lost under different situation
- Recover files from internal and external hard drive (USB, SD Card, Media Player)
- Support file recovery on 200+ formats: video, audio, photo, docs, etc.
- Repair video files in mp4, mov, avi, mkv, m4v and other formats
- Support various file systems: APFS, NTFS, HFS, FAT, etc.
- Preview files before recovery
- Recover files to local drive or cloud platforms
- High recovery rate
How to Recover Data After macOS Downgrade from Big Sur to Catalina?
- Download and install Cisdem Data Recovery to your Mac.
Free Download - Choose the location where you lost the files and click Search for lost files.
- Preview the found files. All the founded files will be categorized in different folders, check the file and preview before recovery.
- Select the found file and recover them onto your mac.Check the box before found files, stop the scanning process if you want to recover before the end of a scanning process. Click Recover to get all lost files after macOS Big Sur downgrade back to your mac.
Conclusion
No matter you want to downgrade from Big Sur to Catalina or Mojave without losing data, or just want to upgrade from an earlier version to the latest macOS, the backup process is mandatory in case of any data loss. If a data loss happens and you don’t have a backup, you will need a dedicated program like Cisdem Data Recovery to do the job.
Connie Wisley
Connie has been writing for Mac productivity and utility apps since 2009. Each review and solution is based on her practical tests, she is aways energetic and trustworthy in this field.
FAQs
How do I downgrade my Mac to Catalina without losing data? ›
- First, restart your Mac using the Apple > Restart option.
- As your Mac is restarting, press the Command + R keys and hold them until you see the Apple logo on the screen. ...
- Now click on the “Restore from a Time Machine Backup” option on the screen and then click on the Continue button.
Can I Downgrade my macOS without Losing Data? Yes, you can downgrade your macOS without losing data if you have a Time Machine backup or a backup on an external device. During the downgrading process, your Mac will ask to copy files from the backup. You can select that option to restore your data.
How do I downgrade to Big Sur without time machine? ›- Shut down your Mac.
- Power on your computer and immediately hold Shift + Option + Cmd + R. ...
- Once the macOS Utilities screen loads, choose Reinstall macOS (or Reinstall OS X) and click Continue.
- Follow the prompts and choose your startup disk.
If you are wondering whether upgrading your macOS to the new version will delete everything, the answer is no. Upgrading your Mac will not delete any photos, files, or other data. However, it's always better to have a backup plan in case something goes wrong.
How do I downgrade my Mac using Time Machine? ›- Plug your Time Machine disk into your Mac.
- Restart your Mac.
- If you have an Intel Mac hold down Command + R until the Apple logo appears. ...
- When the options appear on screen, choose 'Restore From Time Machine Backup' and click Continue.
While it isn't normal for the Mac to slow down after a system upgrade, it has been known to happen. If you're one of the unlucky ones experiencing a slowdown, perhaps slow startups, logins, or application launches, maybe your Mac is just performing poorly in general.
How do I wipe my Mac and install Catalina? ›Choose Apple menu > Shut Down, press and hold the power button until “Loading startup options” appears, select Options, click Continue, then follow the onscreen instructions. In the Recovery app window, select Reinstall for your macOS release, click Continue, then follow the onscreen instructions.
How can I reinstall macOS without erasing data? ›Reinstalling macOS does not remove data from your Mac. To begin installation, select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the onscreen instructions.
Can I skip over macOS versions? ›Yes you can, within limits. For example, if with your Mac Pro you wanted to upgrade to Lion you would have to install Snow Leopard first because the Lion download requires SL.
How do I uninstall an update on my Mac? ›- Go to Apple menu > Restart.
- Press and hold Command+R until you see the Apple logo.
- Choose Reinstall macOS from macOS Utilities.
- The version of macOS that came with your Mac will be installed, and you can then download updates from Apple to update it to the version you want.
How do I get old versions of macOS? ›
- Open the Mac App Store (choose Store > Sign In if you need to log in).
- Click Purchased.
- Scroll down to find the copy of OS X or macOS you want.
- Click Install.
macOS Recovery is the built-in recovery system on your Mac. You can use the apps in macOS Recovery on an Intel-based Mac to repair your internal storage device, reinstall macOS, restore your files from a Time Machine backup, set security options, and more. Reinstalling macOS requires an internet connection.
Can I downgrade my macOS without Time Machine? ›IMPORTANT: Do not downgrade your Mac without first making a complete Time Machine backup on an external hard drive. Downgrading requires completely erasing your startup disk. Without the backup, you will lose all your data, not to mention having to reinstall all your apps separately.
How do I undo macOS Big Sur update? ›Use the Shift + Option + Command + R keys to boot your Mac in Recovery Mode and select the Reinstall macOS Big Sur option from the Utilities selector options. For Macs that didn?t come with macOS Big Sur preinstalled, you will need a bootable macOS Big Sur USB installer.
Does Big Sur slow down your Mac? ›Some Mac users feel macOS Big Sur is slower, lagging, or has worse performance on their Macs compared to prior versions of macOS system software.
Do you need to backup Mac before installing Catalina? ›Tips for Backing up Mac for macOS 10.15 Catalina Upgrade
Hence it is necessary to back up all your data. Not only that, it is always recommended to backup before you upgrade for the latest version. Once again, you don't know what the outcome of your upgrading would be. Things can get better or worse.
- Check compatibility.
- Check for 32-bit apps and Catalina support for other critical apps.
- Back up your Mac.
- Download and install Catalina.
To maintain information security at HMS, we will no longer support macOS Catalina after October 30, 2022. We will continue to support macOS Big Sur and Monterey. Find out which version of macOS you are using by following Apple's instructions.
Is Catalina better for older Macs? ›Mojave supported mid-2010 or mid-2012 Mac Pro models with Metal-capable graphics processor, unfortunately, Catalina won't support those older Mac Pros. Catalina is supported on the following Macs: MacBook models from early 2015 or later.
Why macOS Catalina is the best? ›Catalina has more major new features than we've seen in past macOS upgrades. There are a few new apps, and several other apps with major new features and UI revisions. Performance has been improved and usability has been increased.
How do I prepare my Mac to upgrade to Catalina? ›
Go to Software Update in System Preferences to find the macOS Catalina upgrade. Click Upgrade Now and follow the onscreen instructions to begin your upgrade.
Which disk should I install macOS Catalina? ›If you are running macOS Catalina, Big Sur or Monterey you will have two volumes: Macintosh HD and Macintosh HD – Data. If you want to do a clean install of macOS over an existing installation you will need to first delete the Macintosh HD – Data volume.
Does Time Machine backup everything on your Mac? ›Use Time Machine, the built-in backup feature of your Mac, to automatically back up your personal data, including apps, music, photos, email, and documents. Having a backup allows you to restore your Mac from a Time Machine backup if you ever delete your files or can't access them.
What does command R do on Mac? ›Command (⌘)-R: Start up from the built-in macOS Recovery system. Or use Option-Command-R or Shift-Option-Command-R to start up from macOS Recovery over the internet. macOS Recovery installs different versions of macOS, depending on the key combination you use.
Can I back up Mac without erasing hard drive? ›Yes, there are ways to back up the data from your Mac without an external hard drive. For example, you can use an online backup service such as iCloud to backup your computer. Or you can use a third-party app to create a bootable disk image of the hard drive and upload it to an online data storage service.
Does erase my Mac delete everything? ›Erases your content and settings, and any apps that you installed. Erases all volumes (not just the volume you're on). If you installed Windows on your Mac using Boot Camp Assistant, the BOOTCAMP volume is also erased. Erases all user accounts and their data (not just your own user account).
Can I uninstall Big Sur and go back to Mojave? ›The easiest way to downgrade from macOS Big Sur is by formatting your Mac and then restoring it from a Time Machine backup that was made prior to the installation of macOS Big Sur.
What happens if you downgrade macOS? ›If you have a Time Machine backup from before you updated your Mac to a newer macOS it's quite easy to revert to the old version–but you will lose any new data you have created since the update, so we recommend that you save things like new files and photos to an external drive before you revert using Time Machine.
Can I have 2 operating systems on my Mac? ›To switch between installed macOS versions, just start up your Mac from the other volume. You can do that by changing your Mac startup disk. When you first start up from a new volume, a setup assistant helps you to create a new user account.
When should you stop updating Mac? ›When do Macs become obsolete? Based on operating system support, the limit is between eight and ten years – after which time Apple will not support the software and it's probably a good time to replace your Mac.
Why did my Mac update and delete everything? ›
If you updated your Mac and deleted everything, this can be caused: macOS installed unsuccessfully or interruptedly. Excessive disk fragmentation leads to the damage of hard drive. Mac hard drive doesn't have enough storage space for missing files.
Can I uninstall the latest Apple update? ›Remove and download the update again
Go to Settings > General > [Device name] Storage. Find the update in the list of apps. Tap the update, then tap Delete Update.
The latest version of macOS is 13.2.1. Learn how to update the software on your Mac and how to allow important background updates. The latest version of tvOS is 16.3.3 for Apple TV 4K (3rd generation) and 16.3.2 for Apple TV 4K (1st generation), Apple TV 4K (2nd generation), and Apple TV HD.
Is macOS Catalina still available for download? ›Yes, and here are the steps to upgrade to macOS Catalina: Open the System Preferences menu and select Software Update. Click the Upgrade Now or Download button to start downloading the Catalina installer.
Should I update my Mac to Catalina? ›While most users have reported that the new software runs fine on their device, there are some bugs like Wi-Fi connectivity difficulties, network sharing problems, app errors, etc. If these bugs would hinder your work, you might want to delay upgrading to Catalina until a newer version irons these bugs out.
Can I download macOS Catalina for free? ›And just like Windows 10, upgrading to the latest version is completely free. You can grab Catalina simply by loading the Mac's App Store — the only cost is your time and bandwidth. Below, you'll find our easy step-by-step instructions on how to download MacOS Catalina 10.15.
Does internet recovery reinstall macOS? ›You can use macOS Recovery, the built-in recovery system on your Mac, to reinstall macOS. macOS Recovery keeps your files and user settings intact when reinstalling. Important: Your computer must be connected to the internet to reinstall macOS.
How much data does Mac internet Recovery use? ›So booting once to Internet Recovery Mode requires the download of about 650 MB and restoring your original operating system – which depends on your MacBook Air model – requires an additional download of about ~4.7 GB (Lion) to ~5.7 GB (Yosemite).
Does my Mac have internet recovery? ›How to Enter Mac Internet Recovery Mode. In order to enter this recovery mode via keyboard, press and hold Command-R while your system is booting up. This is a different process than a general update for your Mac.
Can you go back to macOS Catalina? ›You can install Monterey, Big Sur, Catalina or an older version of macOS on your Mac. You will need to wipe your Mac first, which could mean you will lose your data if you don't back it up. Remember backing it up with Time Machine won't be useful here as you would recover Ventura along with your data.