This page covers 5 fixes for Mac won't boot or start issue after macOS Big Sur, Catalina, Sierra or older macOS update issue. If you are with this issue, follow to make your Mac computer work now:
A bootable version of the macOS Catalina installer is one of the often-overlooked tools a Mac user should have on hand before upgrading to or performing a clean install of Catalina. The bootable installer you create in this guide will be housed on a USB flash drive, but you can use any bootable device you may have lying around, including.
|Workable Solutions||Step-by-step Troubleshooting|
|Fix 1. Fix PRAM/NVRAM||Restart Mac > Hold Command+Option+P+R keys to turn on Mac...Full steps|
|Fix 2. Reset SMC||Shut down Mac > Unplug all cables > Plug in cables back after a few minutes...Full steps|
|Fix 3. Boot in Safe Mode||Start Mac > Hold 'Shift' until the login window appears > Release the key when login in window appears...Full steps|
|Fix 4. Run Disk Utility||Turn of Mac > Hold Command + R keys and power Mac back up > Enter recovery mode...Full steps|
|Fix 5. Reinstall macOS||Download macOS Catalina, Mojave, or Sierra > Create bootable USB > Clean install macOS...Full steps|
macOS has now been updated to 11.0, and many Mac users are trying to upgrade to the newest version. While for most it's a usual pleasurable experience, for some this update had downsides. Some users complain that their Mac computers won't boot after installing new macOS Big Sur/Catalina. When Mac fails, it usually can't boot or start up properly. If you are faced with this situation, the most important thing should be recovering data from the unbootable Mac because:
EaseUS Mac data recovery software is able to recover data from unbootable Macs after update. It creates a bootable media that enables you to recover data from Mac hard drive (If you only have one Mac). What's more, it recovers data from failed internal Mac hard drive, APFS boot drive, and unmountable APFS boot volume, etc. If you have two Mac devices, take out the hard drive and connect it to the other Mac. Download EaseUS Data Recovery Wizard for Mac on that Mac device, and recover data from the hard drive.
Then, you can read on and Fix the 'Mac won't boot after update' issue after you have successfully got data from the drive.
NVRAM refers to special memory sections on your Mac that store data that persists even when the Mac is shut off, such as volume settings and screen resolution. Resetting that data isn't harmful! In some cases, after performing this step, your Mac will restart normally.
You may see a progress bar on startup. If the progress bar fills up and then the Mac starts up, you're probably good to go. If not, reset SMC.
In some situations, you may need to reset your Mac's SMC (System Management Controller).
If you've got a Mac desktop, unplug it for 15 seconds and then plug it in and after five seconds press the power button.
Safe Mode is a stripped-down version of the Mac operating system that can be useful if you are trying to troubleshoot issues with your Mac.
Wait patiently till Mac computer finish the reboot process.
If your Mac is booting but the operating system isn't loading up, you may have a corrupted drive. Luckily it is possible to fix this in Recovery Mode. In Recovery Mode you can restore from a Time Machine backup, use Disk Utility to verify and repair connected drives, check your internet connection, get help online using Safari, and install or reinstall macOS.
The last method to fix macOS Big Sur, Catalina or Sierra fails to boot after update error is to reinstall macOS.
If your Mac does not respond after trying these tips, contact Apple Support or a certified Apple Repair Center. It’s likely there is a problem with your logic board or other internal hardware.
So many of you are in confusion that should I upgrade my MacBook Air or MacBook Pro or I Mac to latest Catlina OS by Apple.
MacOS Catalina will be the next major version of the Mac operating system. Versioned as MacOS 10.15, Catalina includes a variety of new features, improvements to bundled apps like Safari, Photos, Reminders, and Notes, the splitting of iTunes into several new apps, and some intriguing new features and capabilities that bundle well with iOS 13 on iPad (now called iPadOS).
Apple continues to roll out small updates to macOS Catalina months after the initial release. These small updates include important fixes and small new features. In most cases, the small updates are worth installing soon after release, but you may still want to wait a few days, just to make sure everything is working fine with the upgrade. This guide can help you decide if it is worth installing right now.
You can downgrade to macOS Mojave from macOS Catalina if you don’t like it. There is no time limit like on iOS 13, but it is a process and takes some time so do your research before you upgrade.
Find out if your Mac can run macOS Catalina Here
There are many good reasons to install macOS Catalina on your Mac today or to install the macOS Catalina 10.15 update. Before you start, you need to consider these reasons you shouldn’t upgrade yet. If you are already on macOS 10.15, it’s a good idea to install the supplemental update.