The below is taken from https://www.maketecheasier.com/fix-frozen-mac-when-updating-macos.
1. Install the Update in Safe Mode
Updating your Mac to Catalina should not result in the loss of any files unless you erased the drive while installing Catalina. If you see no files in your Documents folder and you did not do an erase and install, something is wrong with your file system. How to repair a Mac disk with Disk Utility - Apple Support. Upgrading from Mac OS X Older Versions. Any older versions of Mac OS X 10.7-10.10 have to first upgrade to Mac OS X El Capitan 10.11 version before upgrading to macOS Catalina, which you can download from Apple’s Catalina download page. To do this, follow these steps: Launch the System Preferences menu, and thenselect Software Update.
Most of the time, macOS should be able to resolve these issues gracefully, but occasionally it may cause your Mac to lock up halfway through the update. If your Mac encounters difficulties when downloading or installing the latest release, don’t panic! In this article, we share seven fixes that can fix your frozen Mac and get it back on track. As we warned back in June, older Office for Mac will not work with MacOS Catalina. If you have Office 2011 for Mac or before, do NOT update to Catalina because Office will stop working. There’s no workaround for this. Office 2016 for Mac needs to be v15.35 or later, which it probably is, if you’ve updated anytime in the last few months.
If it’s clear that your Mac update isn’t going anywhere, then hold down the power button to turn off your Mac. Once you’ve done this, boot your Mac into Safe Mode. There are several ways to do this, but the simplest is by holding the Shift key as it’s booting.
The Apple logo should appear on your screen with a loading bar, and after that you should boot into Safe Mode. From here, run the macOS update as you normally would to install the update – hopefully without a hitch.
2. Check the Apple Systems Status Page
A very quick and easy thing to do that could save you a lot of hassle with stuck updates (or other malfunctioning Apple services) is to go to the official Systems Status page. Here you’ll see the status of just about every Apple service you can think of. Look over at the status of “macOS Software Update” to see whether the update servers are working as they should. If the bubble is green, then they’re fine and the issue lies elsewhere. If it’s red or yellow, then you’re just going to have to sit out the problem until servers are back to normal.
Speaking of sitting it out…
3. Sit it Out
As painful as it sounds, you may just want to let the Mac sit for a couple of hours and see if it is indeed frozen. Sometimes, the update could be stuck in a lull but not completely frozen. Some update processes will take much longer than others, resulting in a seemingly stuck progress bar.
We can verify that the system is still updating by pressing Command + L to bring up the estimated install time. If this doesn’t appear, still let the update sit for a while.
Some users have reported their update taking upwards of ten hours. Grab a coffee, do some other work, run some errands, do whatever you need to do to burn some time and let your Mac do its thing. Big system updates (sometimes) take a whole lot of time!
4. Refresh the Update
If you are positive that the install is indeed frozen, you will want to take the following steps, and the following steps consecutively after this step, until the issue is resolved.
Let’s try to give the install a little kick by refreshing it.
- Hold down the power button and wait for about 30 seconds.
- When the Mac is completely off, press and hold the power button again. Now, the update should resume.
- Press Command + L again to see if macOS is still installing.
If there is no avail, continue onto the next solution below.
5. Reset Your NVRAM
NVRAM, as Apple describes it, is “a small amount of your computer’s memory that stores certain settings in a location that macOS can access quickly.” It also happens to hold kernel panic information, which is what we’re tapping into and especially trying to reset here.
- Press and hold the power button on your Mac to completely shut it off. Hard discs and fans need to stop spinning, and the screen needs to go dark.
- Power on your Mac.
- Immediately after you hear the startup sound, press and hold the Command + Option + P + R keys.
- Keep holding them down until you hear the start up sound again.
- Release the keys, and the NVRAM will have reset. The update should resume.
Does your iMac, Mac Pro, MacBook Air, MacBook Pro, or MacBook stuck on login screen after update to Big Sur, Catalina, Mojave or High Sierra? That Mac won’t boot is not a new issue but still a tough call for ordinary users to fix it. Well, this article will walk you through the solutions to solve “Mac stuck on boot screen after Big Sur or Catalina update” problem.
File Missing after Mac Stuck on Login?
- Recover files missing or lost due to system upgrade/downgrade,etc.
- Restore formatted, deleted files
- Support recovering data in 200+ formats (audio, video, image, docs, etc.)
- Get back files from mac internal and external hard drive (SD, USB, etc.)
- 5 recovery modes for different situations
- Preview files before final recovery
- Applicable for macOS Big Sur and Catalina
Why Mac Stuck on Login Screen after Update?
- The update of macOS Big Sur or Catalina brings certain incompatibility problem (between Apple default apps and the OS) or unsolved bugs
- Not enough hard drive space
- Corrupted SSD or HDD
- Too many boot items opening at login
- Malware or virus deleted the crucial system files
- File system corruption of Mac partition
- Power issues
- Motherboard Failure
- …
macOS stuck at login screen is a complex issue meaning there’s something bad coming with your Mac system and it needs to be repaired as quick as possible.
The Common Symptoms
The symptoms of “MacBook stuck on login screen after update” issue is different, the familiar ones are those your Mac may stuck on:
- Grey screen
- White screen
- Black screen
- Login loading bar
- Apple logo (loading screen with Apple)
- Startup screen spinning wheel
- Login screen after password
- Startup screen with status bar
Or your Mac:
- Won't boot past apple logo
- Won't load past login screen
- Frozen on the startup screen after macOS Big Sur or Catalina update
- …
By knowing the symptoms, you can safeguard your data to avoid data loss crisis, and then take immediate actions to fix the problem.
How to Fix Mac Stuck on Boot Screen after Update?
Fix 1. Reboot the Mac
Do the most essential things at first, as they don’t require any tech support.
- Shut off your Mac
- Disconnect the whole peripherals except those needed to turn on the system
- Check your charger’s cable (make sure the cable is intact and the port is clean.). If your MacBook stuck on login screen because of battery power, the battery could be thoroughly depleted or malfunctioning.
When everything is ready, boot your Mac with peripherals reconnected.
Fix 2. Reboot Your Mac in Safe Mode
Safe Boot feature is included since Mac OS X 10.2. It minimizes the apps on your Mac to help identify the issue that causes your macOS stuck at login, or any issue correlated with your startup disk. So not only will it restrict your applications, but also check through startup drive.
- Restart your Mac computer.
- Press the Power button while holding down the Shift key immediately.
- Keep it held until you see the Apple logo.
Matters need attention:
- It’s slower to boot Mac in Safe Mode.
- Not all the OS X functions and programs will work when performing Safe Boot (only for troubleshooting).
- Confirm that your Mac hard drive possesses at least 10 GB of free space. If not, empty your Trash bin or move some of largest files & folders to another drive.
Fix 3. Reboot Your Mac in Single User Mode
Just like booting in Safe Mode, the Single User Mode assists to isolate and fix the common problems that can keep your MacBook stuck on login screen from starting up properly. This method is suitable for advanced users who are comfortable with UNIX or has comprehensive knowledge of the command line.
- Turn on your Mac while holding Command + S key simultaneously.
- When you see the white text on a black background, release the keys.
- Enter the administrator password to access to Mac Big Sur or Catalina Single User Mode.
Fix 4. Reset System Management Controller (SMC)
SMC controls a host of important functions in a Mac. It deals with many amusing things, from keyboard backlight, charging, fans, etc. to system performance. That resetting the SMC to original factory settings is an all-in-one solution, which can also fix your iMac, MacBook Air or MacBook stuck on login screen after update.
For desktop Mac, iMac or MacBook:
- Unplug the power cord.
- Wait for 15 or 20 seconds, and plug the power cord in.
- Wait for 5 or 10 seconds, and power on the system again.
- Restart your Mac.
For Mac laptop:
- Make your Mac unplugged, and then turn off the power.
- Hold down the Shift + Control + Option key. At the same time, press and hold down the power button. Hold down all of them for 10 seconds.
- Re-plug the Mac in and reboot it up.
For old Mac laptop with removable battery:
- Shut down your Mac > unplug it > remove the battery.
- Hold down the power button for 5 seconds.
- Put the battery back in > plug the Mac in > restart Mac.
Fix 5. Reset Nonvolatile Random-access Memory (NVRAM) or Parameter RAM (PRAM)
NVRAM is used to store some settings and access them fleetly. PRAM is similar to NVRAM, and shares the same steps with NVRAM. If you experience issues like Mac stuck on boot screen after update to latest macOS, resetting NVRAM/ PRAM may give you a hand.
- Shut down your Mac.
- Turn your Mac, and hold down Option + Command + P + R key together right away.
- Keep holding until your Mac restarts.
Fix 6. Reboot Mac in Recovery Mode
Recovery Mode was offered since OS X Lion in 2011. It shows you 4 options applied to fix connected drives with Disk Utility, restore data from Time Machine, reinstall macOS and get help online. I guess two of them are likely to repair your macOS stuck at login issue.
My Imac Will Not Update To Catalina
Option One. Run First Aid from Recovery Partition
- Turn off your Mac, and then switch it on.
- Immediately hold down Command + R keys till an Apple logo appears.
- Wait for a moment, the OS X Utilities window will show up.
- Click on 'Disk Utility' option.
- Locate your Mac drive, and choose it.
- Click on 'First Aid'.
Option Two: Reinstall macOS
If none of the solutions work out to fix the MacBook stuck on login screen issue, then reinstalling macOS will be the last option.
- Repeat the first three steps of option one.
- Select “Reinstall macOS” from the Utilities window.
- Click on “Continue” and follow the installation process.
Attentions of reinstallation:
- Don’t put your Mac to sleep status.
- Mac would reboot and display a progress bar a couple of times
- After installation, click on “Shut Down” option from the Apple menu to quit Mac Recovery Mode.
Also, you can check the video tutorial as following:
Lost Data after Big Sur or Catalina Update or Issue Repaired? Recoverable!
That Mac stuck on boot screen often comes along with data loss from the hard drive. If you didn’t manage to back up your Mac data before, you won’t be able to recover lost files via Time Machine after macOS upgrade.
Fortunately, Cisdem Data Recovery for Mac- an effective and powerful recovery program, allows you to retrieve a wide range of file formats (Keynote, PDF, JPG, PNG, MOV, RTF, etc.) or any types (video, documents, archive, etc.) of deleted, formatted, corrupted data on Mac. It’s absolutely safe and keeps your data private.
Step 1Install the Software
After the installation, launch Cisdem Data Recovery on Mac.
Step 2Select the Scenario
You will see 5 recovery solutions. To recover lost files after macOS update, you can choose the option 'Basic Data Recovery' (fast scan) or “Advanced Data Recovery” (deep scan) to start performing lost file recovery.
Step 3Choose a Destination
Select the hard disk where your lost files are originally stored and click on “Scan” button” to go on.
Step 4Start to Scan
The “Basic Data Recovery’ mode only takes a minute to finish. If it doesn’t find out your lost data, go to scan again with 'Advanced Data Recovery' mode which searches more files but spends longer time.
Step 5Preview and Recover Lost Files
Once the scanning process is done, all detected contents will be displayed in 'Tree View' categories on the left side. You can preview them for saving your time on data recovering.
Finally, choose the target files and click on 'Recover' button. In no time, your files that lost after “Mac stuck on boot screen” fixed will be retrieved.
Conclusion
My Mac Is Not Updating To Catalina
It can be troublesome and distraught that your MacBook stuck on login screen after update to Big Sur or Catalina. Worse still, you may lose files in the meantime. We introduce 6 practical solutions to get macOS stuck at login issue fixed, along with 1 data recovery program to restore lost files, but the safest plan is to keep backups of all vital files on Mac.