Reinstall Mojave From Catalina

After Catalina is installed, you can switch between Catalina and Mojave using the Startup Disk system preference. Here’s how: 1) Click the Apple menu. 2) Select System Preferences. 3) Click Startup Disk. 4) Click the padlock icon in the lower left corner of the window to unlock the settings. Enter your system password and click Unlock.

Downgrade Catalina to Mojave

I upgraded or rather installed Catalina but I installed it on another partition on my HD. I install or transfer apps, from my Mojave drive onto my Catalina drive. I can now test any app, for functionality and compatibility. If there are issues they can be sorted but I can still rely on Mojave to get on with what I need to do. Lisa, your Mac probably became slow after you upgraded to 10.14 Mojave or Catalina, from 10.13 (High Sierra) or earlier. The reason for it to have become slower is that the upgrade converted your disks from HFS to APFS format. If you are still using hard disks instead of SSDs, then APFS has made them slower, by at least a factor of 2.

If you’ve installed macOS Catalina and run into problems with some of your apps, or you’ve just decided that you don’t like it as much as Mojave, the good news is that you can downgrade back to the previous version of macOS. The bad news is that it’s a lengthy process with several steps. Read on to find out how to do it.

1. Back up your Mac

You should have backed up your Mac before you upgraded to Catalina, as you should before you perform any major upgrade or make any significant change to your Mac. However, the files you’ve been working on since you upgraded won’t be up to date on that backup. So, you should copy those files to an external disk, or a cloud storage service like Dropbox or iCloud Drive so you can retrieve them easily when you downgrade. We’re going to completely erase your Mac’s startup disk, so it’s important to copy anything you need now.

Before you backup, however, you should take steps to remove the junk and clutter from your Mac. There’s no point in backing up all the clutter along with the files you really need. To do that, I recommend CleanMyMac X. It’s the easiest way to clear out the clutter on your Mac. Here are just a few things it can do:

  • Delete years worth of system junk
  • Find hidden apps and folders
  • Neutralize Mac-specific malware, like key loggers
  • Manage hung apps and heavy CPU consumers
  • Update all your software to the latest-supported versions

As you can see, CleanMyMac X does a lot more than just clear out junk files before you backup your Mac. It’s well-worth keeping it on your Mac and using regularly to keep your Mac running smoothly.

2. Save your passwords

When you downgrade mac OS Catalina, you’ll delete everything from your hard drive, including licence keys and settings. So, in addition to making sure you copy all the files that have changed since you last backed up, you should make a note of those. If you use a password manager that syncs with other devices and allows you to store licence codes and encrypted notes, you could use that. If not, any app that allows you to sync encrypted notes will do. Or you can use Apple’s Notes app. It’s also a good idea to take screen grabs of settings to make it easier to restore them later. Remember to copy the grabs to a cloud storage service or an external disk.

Reinstall Mojave From Catalina

3. Create a bootable installer of macOS Mojave

Note, you can skip this step if your Mac shipped with macOS Mojave or if you made a backup with Time Machine before you upgraded to Catalina.

  1. If you’re reading this before macOS Catalina ships, you can go to the App Store and search for Mojave, then download it. If it tries to install when it’s finished downloading, quite the installer.
  2. If you’re reading this after Catalina ships, you can download Mojave ‎here, but only on a Mac that’s not already running Mojave. When you click that link, Software Update will launch and start to download Mojave. When it’s finished, quit Software Update.
  3. Grab a USB stick with 16GB capacity or an external hard drive or SSD and plug it in to your Mac.
  4. Launch Disk Utilities and Erase the Drive or USB stick, formatting it as Mac OS Extended (Journaled) and selecting GUID partition map if a selection is available.
  5. The easiest way to create a bootable installer is to use DiskMaker X. However, you can also do it in Terminal like this:
  • Launch Terminal from Applications - Utilities
  • Type: sudo /Applications/Install macOS Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled where ‘Untitled’ is the name of your USB stick or external hard drive
  • Press Return and wait for the word Done to appear in Terminal.

Whichever method you used, you should now have a bootable macOS Mojave installer. Keep it safe.

4. Uninstall macOS Catalina

  1. Make sure your Mac is connected to the internet.
  2. Click on the Apple menu and choose Restart.
  3. Hold down Command+R to boot into Recovery mode.
  4. Choose Disk Utility in the macOS Utilities window
  5. Select your startup disk
  6. Choose Erase
  7. Quit Disk Utility
Reinstall Mojave From Catalina

How to downgrade Catalina to Mojave if your Mac shipped with Mojave

  1. Once you’ve erased your startup disk and quit Disk Utility as described above, choose Reinstall macOS from macOS Utilities.
  2. Press Continue.

How to rollback from Catalina using a Time Machine backup

If you backed up your Mac with Time Machine before you installed Catalina, you don’t need to create a bootable installer – you can just reinstall Mojave from your Time Machine backup. Make sure it’s plugged in if it’s an external disk. If it’s a network disk, make sure you’re connected to the network.

  • Once you’ve erased your start up disk as described above, choose Restore from Time Machine backup in the macOS Utilities window.
  • If your backup is on an external disk, select it. If it’s on a network disk, select it and choose Connect to Remote Disk.
  • Type in your username and password for the remote disk if necessary.
  • Select the data and time of the backup you want to restore from.
  • Follow the onscreen instructions.

5. Install Mojave using a bootable installer

If you have a Mac that didn’t ship with Mojave and you don’t use Time Machine to backup, you’ll need to reinstall Mojave from the bootable installer we created earlier.

  1. Plug in the installer disk.
  2. Go to the Apple menu and choose restart, then hold down the Option key.
  3. Mojave will start installing on your Mac.
  4. When it’s finished, your Mac will restart and the Setup Assistant will appear
  5. Follow the steps in the SetUp Assistant to set up Mojave

Restore your settings

If you have reinstalled Mojave from a bootable disk, rather than a Time Machine backup, you will need to reinstall applications and copy documents across from your backup. That’s where those notes and screen shots you made earlier come in handy!

Once you’ve restored your settings and reinstalled all the apps you need, your Mac is ready to use again, running Mojave instead of Catalina.

Tip: If you want to roll back to an earlier version of macOS than Mojave, you can. To reinstall the OS your Mac shipped with, use the method in ‘How to downgrade if your Mac shipped with Mojave’. If you want to roll back to a version of macOS newer than the one your Mac shipped with but older than Mojave, you can download Sierra and earlier versions from the Mac App Store. Then follow from Step 3 in ‘Create a bootable installer of Mojave’.

My Mac is still underperforming, what to do?

You thought that reverting to macOS Mojave would get your Mac back to norm. But if it didn’t and you still experiencing sudden freeze-ups and glitches, full disk cleanup is your answer. Probably there are too many conflicting system junk files on your drive that you need to plow through.

You don’t need a regular disk cleanup app — most of them are scam — but this tool, CleanMyMac X, is notarized by Apple, and can really do helpful optimizations on your Mac.

  • Download the free edition here
  • Go to Maintenance tab


Now you can perform some of the tasks suggested by the app, like running Maintenance Scripts. Also, check the System Junk tab and remove all the useless files it recommends you to delete.

As you can see, it is possible to uninstall Catalina if you decide you don’t want to continue using it. It’s essential, however, that you backup your Mac before you upgrade. And remember, before you backup, clear out the clutter with CleanMyMac X. That way you won’t use precious space on your backup drive copying over junk files.

Jul 05, 2021 • Filed to: Solve Mac Problems • Proven solutions

There are many issues that people may encounter while installing the macOS update. One of the common problems is that the recovery server could not be contacted. When trying to install macOS High Sierra, Mojave, or Catalina, there is an error message popping up: The recovery server could not be contacted.

If your macOS update is also stopped by this error, you will find this post helpful. From this post, you will learn why the recovery server could not be contacted and how to fix it.

What Does It Mean When the Recovery Server Could Not Be Contacted?

When installing a macOS update with a macOS installer, your Mac needs to reach the Apple server. When it says 'the recovery server could not be contacted, it means that your Mac failed to build a connection with the Apple server.

There are multiple culprits behind this issue.

  • Your Mac is disconnected from the network. A stable network connection is required for your Mac to successfully contact the Apple server.
  • The date and time on your Mac are not properly synced with the Apple recovery server.
  • The Apple server is overloaded with too many users trying to installing the new update at the same time. Whenever there is a macOS update recently released, the Apple server usually experiences a busy time.

Solution 1: Check Network Connection on Mac

Firstly, you need to check if your Mac is connected to a proper internet connection. If your Mac is on a wired internet connection, you can re-plug the Ethernet cable to check.

If your Mac is using a Wi-Fi, you can access the Wi-Fi option from the top right corner of your screen to check it is connected to a stable Wi-Fi network.

The faster the internet, the quicker you can access the Apple recovery server.

Solution 2: Sync your Mac' Date and Time to Apple Recovery Server

If your Mac's date and times are not synced to the Apple recovery server. You can update these settings by utilizing these steps;

Step 1: First of all, close the error. This will open the macOS Utilities window.
Step 2: Next, you are required to choose the option 'Utilities' on the top menu bar.
Step 3: You will see the option 'Terminal', double click on it.
Step 4: Then type the following command line: 'ntpdate -u time.apple.com' and press enter.
Step 5: The above step might take some time. Once the process is completed, you can try reinstalling the macOS update again. Hopefully, your problem will be solved.

Also if the 'ntpdate -u time.apple.com' command-line failed to fix the recovery server could not be contacted on your Mac, you can try the following command.

  • Open Terminal.
  • Enter date. And hit Enter key. This will show the date of your Mac.
  • If the date and time are wrong, you should enter the current time with the following command line: date mmddhhssyy. For example, if it is July 20, 09:00 am, 2020, you should enter: date 0720090020 (July 20, 09:00 am, 2020,).
  • After that, quit Terminal and click Reinstall macOS to run the Catalina/Mojave installer again.

Solution 3: Install the Full Version of Mojave/Catalina Installer

Some users found that when they try to install a macOS update with the update installer from App Store, it just showed the error message 'the recovery server could not be contacted. However, after downloading a full version of the macOS installer, the installer can run without any error. Here is how you can get a full version of the macOS Catalina update.

Step 1Run Terminal.

Step 2For example, to download the full version of the macOS Catalina 10.15.3 Installer Application, enter the command line as below.

  • softwareupdate --fetch-full-installer --full-installer-version 10.15.3

Step 3The installer will be downloaded in the Application folder.

Step 4Run the installer to install the macOS without the recovery server error.

Solution 4: Erase Your Disk and Reinstall macOS

In case you have utilized all the above methods and have not received any good results. Only then, you can erase your hard disk and reinstall macOS. You can enter the recovery mode to erase the hard disk. After that, reinstalling macOS can solve your problem. Follow the steps properly erase your hard disk and reinstall macOS;

Step 1Firstly, you need to restart your Mac.

Step 2When the Mac is starting, you need to press and hold CDM + R keys to enter the recovery mode.

Step 3In the Recovery mode, click Disk Utility and erase the Macintosh HD volume. This will delete all your data on your Mac so make sure you have backed up your important data.

Step 4After erasing your disk, you can reinstall macOS. This time, you won't see the recovery server could not be contacted error.

If you have important data missing after the macOS update, you can get it back by using Recoverit Data Recovery software. The program is designed to recover photos, documents, videos, emails, etc. from the Mac computer after the data are deleted mistakenly or lost because of macOS reinstallation, factory reset, or virus.

Lost data can be recovered in 3 simple steps by Recoverit: select the drive of lost data, scan the drive, recover the files.

Download the free trial version of Recoverit Data Recovery to scan and find your needed files.

Conclusion

Many users complained about the recovery server could not be contacted error. Every error is solvable, only if you apply proper solutions. And to tackle the incidents that may happen in the macOS update, you need to back up your data before implementing any of the steps. In case your data is lost, you can recover it using Recoverit Data Recovery.

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