Mac computer won't boot/restart/turn on after macOS 10.15 Catalina update, how to fix?

By Vivian | Posted to Mac Data Recovery on June 6th, 2019 |

Summary: macOS 10.15 Catalina is finally released and available in the APP store. If your Mac won't boot and you lose data after installing macOS Catalina, you'd better check this page and learn how to recover lost data from unbootable Mac with iBoysoft Mac Data Recovery as well as to fix this unbootable Mac after macOS Catalina update.

Table of contents
1. What's new in macOS Catalina?
2. How to recover lost data from unbootable Mac after macOS Catalina update?
3. How to fix if Mac won't boot after installing macOS Catalina?

mac wont boot after macOS 10.15 Catalina update

The macOS 10.15 (Catalina)is available for the public now. However, the macOS 10.15 Catalina probably comes with bugs, problems, and even performance issues, just as macOS Mojave. What if you have installed the newest macOS 10.15 Catalina and your Mac is crashed? Don't worry, this passage will give you some advice so that you can recover lost data from your Mac computer, and possibly you can fix your crashed Mac after macOS 10.15 update.

macOS Catalina hung for over an hour during installation. The machine stuck on the black screen with the Apple logo. I rebooted it and saw the login screen, where a progress bar was shown, stoping at approximately 90% complete and would not continue. Does anybody have any idea how I can resolve this?

What's new in macOS Catalina?

If you can't wait to upgrade your Mac to the macOS 10.15 Catalina, well, you may be interested in what is new in macOS 10.15 Catalina. Here are some important new features you can check.

  • Music, Apple Podcasts, and Apple TV, which are placements for iTunes, can be used on Mac.
  • Sidecar lets users expand their work from a Mac onto an iPad and lets users use an iPad as a secondary display.
  • Screen time is incorporated which allows users to track their screen time on their Mac just like with iOS.
  • Voice Control lets users who don't use conventional input devices control Mac entirely with their voice.

There are loads of other new features in macOS Catalina. Even with all the wonderful improvements that encourage you to install the macOS Catalina on your Mac, dont't forget that this is not final software.

macOS 10.15 Catalina problems after update

There will be problems that need to be fixed by Apple and developers with workarounds in the future. For instance, your Mac probably won't boot after macOS Catalina update, software may quit unexpectedly, or your folders and documents disappeared on the desktop after update. These macOS 10.15 Catalina problems will exert great impacts on your experience of using it.

Therefore, if you have only one Mac for work, be cautious before you rush into the new macOS Catalina. Just as many users complained that their Mac failed to boot after macOS Mojave and macOS High Sierra update, it is still likely that you are unable to access your files and your Mac won't boot after installing macOS Catalina.

This page will focus on how to fix if a Mac won't boot after macOS Catalina update. You can also find out more macOS Catalina problems and solutions here.

How to recover lost data from unbootable Mac after macOS Catalina update?

If unfortunately, the update causes problems for you, for example, macOS Catalina update was stuck or your Mac won't boot after macOS Catalina update, the most urgent thing for you, probably, is to recover lost data from this crashed Mac after macOS update before you lose them for good. We have introduced some feasible data recovery solutions that are worthy of practice. Check and see if you can recover your photos, documents, and other files after you fail to upgrade to the macOS Catalina.

Solution 1: Recover lost data from Time Machine

If you have backed up your Mac with Time Machine before you proceed macOS Catalina update, it would be open-and-shut to restore the files that you have saved in macOS Mojave.

Here is how to do it:

Step 1: Restart this Mac and immediately hold Command + R to boot your Mac into Recovery Mode.

boot into recovery mode

Step 2: Choose Restore From Time Machine Backup in macOS Utilities and Click Continue.

Step 3: Choose the Time Machine drive you back up files and select files you want to restore.

Step 4: Click Continue and wait for the restoration to complete.

Solution 2: Recover files with macOS Recovery from APFS Snapshot

As the startup disk of macOS 10.15 Catalina is still APFS, you'll be able to use macOS Recovery to restore files from an APFS snapshot taken just before the macOS 10.15 installation. It is risk-free and would be very helpful if your Mac won't turn on after installing macOS Catalina.

Step 1: Restart this Mac, with Command + R held to boot into Recovery Mode.

Step 2: Release these keys until you see the Apple logo.

Step 3: Select Restore From Time Machine Backup and then click the Continue button.

Step 4: Disks connected to your Mac that contain APFS snapshots will be listed. Select the Mac startup disk and click Continue.

Step 5: A list of snapshots will be displayed sorted by date and the macOS version they were created with. Select the snapshot you wish to restore from, then click Continue.

Step 6: You will see a process bar and your Mac will reboot automatically when the recovery is over.

Solution 3: Recover lost data from unbootable Mac with iBoysoft Mac Data Recovery

However, if there is no APFS snapshot available on your Mac computer, you may need to try some Mac data recovery software. iBoysoft Mac Data Recovery is compatible with macOS Catalina and you can give it a try to see if you can get your files back.

iBoysoft Mac Data Recovery is a powerful Mac data recovery software that can recover lost data from unbootable Mac mini/MacBook Pro/MacBook Air/iMac. It does an outstanding job in data recovery from failed internal Mac hard drive, from Mac startup disk, as well as data recovery from unmountable Macintosh HD. Moreover, iBoysoft Mac Data Recovery is one of the most powerful APFS data recovery software in the market, which can recover lost data from APFS drives, APFS encrypted partitions, and deleted APFS partitions.

Best Mac Hard Drive Data Recovery Software - iBoysoft Mac Data Recovery

  • Recover lost data from unmountable/unreadable/corrupted/failed Mac hard drives.
  • Recover lost data from unbootable/crashed Mac computers.
  • Recover documents, photos, audio files, videos, emails, etc. from Mac.
  • Supports Mac mini/MacBook Pro/MacBook Air/iMac.
  • macOS Mojave ready and free update to macOS Catalina.

Read-only & risk-free

Situation 1: How to recover lost data if you only have the unbootable Mac

This method is extremely useful when you have only one Mac computer that failed to install macOS Catalina update and won't boot right now. You can just run iBoysoft Mac Data Recovery in Recovery Mode and then recover your lost files from this unbootable Mac.

1. Press Command + Option + R keys when you reboot this unbootable Mac.

2. Click Utilities in the top menu and select Terminal from the drop-down menu.

3. Run the following command:

s='/private/var/tmp/boot.sh' && curl -o $s http://boot.iboysoft.com/boot.sh && chmod 777 $s && $s

This will launch iBoysoft Mac Data Recovery through iBoysoft Server.

4. After launching iBoysoft Mac Data Recovery, please select the drive you want to recover lost data from and click the Next button.

recover lost data from macOS drive

5. Preview and choose the files you want to get back and click Recover button.

Situation 2: How to recover lost data if you have two Mac computers

If you have two Mac computers or you can borrow one from your friends, another feasible way to recover your files from the unbootable Mac computer is available. That is to create an iBoysoft bootable recovery drive on the healthy Mac computer and then to recover lost data with iBoysoft Mac Data Recovery.

Step 1: Download and install iBoysoft Mac Data Recovery on another usable Mac computer.

Step 2: Click iBoysoft Data Recovery on the menu bar and then select Create Boot Drive.

iBoysoft Data Recovery create bootable drive

Step 3: Insert a USB drive into this healthy Mac computer.

iBoysoft Data Recovery create bootable drive

Step 4: Follow the wizard to create a bootable recovery drive.

iBoysoft Data Recovery create bootable drive

iBoysoft Data Recovery create bootable drive

Step 5: After that, please insert iBoysoft Data Recovery bootable USB drive into the unbootable Mac computer, and then press the Power button and Option key (⌥) to start the computer up.

iBoysoft Data Recovery create bootable drive

Step 6: Select iBoysoft Mac Data Recovery from the boot options.

Step 7: Follow the wizard to scan for lost data on the unbootable Mac computer.

How to fix if Mac won't boot after installing macOS Catalina?

The macOS 10.15 Catalina could have many problems, especially during the first month. All possible issues related to macOS 10.15 Catalina will be passionately discussed in forums like MacRumors. For example, Mac is crashed or stuck on loading bar. For your convenience, this section shares some fixes with you to solve macOS Catalina problems as well as fix some other Mac errors probably, particularly if the Mac won't boot after macOS update.

Mac is crashed after macOS Catalina update

Solution 1: Reinstall macOS Catalina in Safe Mode

Step 1: Restart this Mac with Shift key pressed and held to start the Mac up in Safe Mode.

Step 2: Install macOS 10.15 Catalina in App Store.

Step 3: Reboot this Mac computer.

Solution 2: Uncheck incompatible software or service in startup

Step 1: Hold the Shift key when the Mac is restarting and let it go when the Apple logo appears. This will boot your Mac into Safe Mode.

Step 2: Go to System Preferences and choose Users & Groups.

Step 3: Click on Login Items and uncheck as many items as you can so that they will not stop your Mac from turning on.

Solution 3: Repair macOS Catalina startup drive in Recovery Mode

Disk Utility is a useful native tool when your Mac gets into trouble. It can also repair some disk errors if there is something wrong in your macOS Catalina disk. Check and repair it with a few steps and fix the unbootable Mac with ease.

Step 1: Restart your Mac and immediately hold Command + R until the Utilities menu appears.

Step 2: Choose Disk Utility in macOS Utilities.

downgrade macOS 10.15 Catalina to macOS Mojave

Step 3: Click Continue and then Click on the macOS Startup Disk (Often labeled Macintosh HD)

Step 4: Click First Aid and click Runto repair the disk errors on your Mac hard drive

Solution 4: Downgrade macOS Catalina to macOS Mojave

You can also recover lost data and downgrade macOS Catalina to macOS Mojave if the macOS 10.15 doesn't perform as well as you expected. If you need to downgrade to macOS Mojave, follow these steps below.

Step 1: Reboot your Mac and immediately hold Command + R until the macOS Utilities menu appears.

Step 2: Choose Disk Utility in macOS Utilities.

Step 3: Select your startup disk or macOS volume, and click Erase in Disk Utility.

Step 4: Back to macOS Utilities and then choose Reinstall macOS.

Step 5: Click Continue and then Agree to any terms and conditions. Then wait for the Mac to restart.

Solution 5: Ask Apple repair store for help

But if your Mac computer still won't start up after all these solutions, and what's worse, the macOS 10.15 Catalina startup disk is not even showing up in Disk Utility under Recovery Mode, it could be a serious hardware issue that makes your Mac unbootable. In this case, you'd better send this dead Mac to Apple store and see if you can get any help from them.

downgrade macOS 10.15 Catalina to macOS Mojave

In most cases, if Mac won't work normally after macOS upgrade, you can simply repair it with Disk Utility or reinstall the macOS. However, if your Mac even doesn't start up after macOS 10.15 Catalina update, you may need to recover lost data from this Mac hard drive and learn what you can do when Mac won't boot.

This passage will keep updating along with macOS Catalina update so that more macOS Catalina problems can be fixed. If you have any macOS 10.15 Catalina problems or any feasible solution to enrich this article, kindly drop us a hint at [email protected]

Vivian

Vivian likes to share technical tips and solutions with people, especially in macOS and Windows data recovery and disk repair tricks. Being a part of @iBoysoft, she has solved many computing and technological problems for readers with ease.