Mac Not Booting after Sierra Update - Fixed

Apple recently released an updated macOS Sierra 10.12.2 version for Mac computers. Many users are trying to get beta version for their Apple devices to get latest new features. But, some users complain that their MacBook or Mac won’t start up after installing new macOS Sierra.

If you are having the same problem that your MacBook hangs on a grey screen with an Apple logo and fail to boot, then here are effective methods to help you in updating to macOS Sierra without data loss on your Mac now.  

Now let’s see how to fix MacBook / Mac won't boot after update Sierra is installed

Before continuing through any troubleshooting tips mentioned below, the first thing to do is backup up all your data from your Mac hard drive to ensure that it’s safe. Please try each of the solution explained here until your problem is solved:

  • Click and hold the Power icon for a few seconds until your Mac turns off. Wait for few seconds and press Power button to turn on your Mac.
  • Try to start your Mac using Safe Mode. Steps to do this, turn on Mac and click Shift key when you hear the startup sound, then release it when you see the Apple logo. Restart your system and wait patiently till it complete the reboot process.
  • Launch Mac and press Command + R as it starts up. Press Disk Utility -> click on First Aid option and try fixing your Mac drive. Here Disk Utility automatically run fsck to fix macOS Sierra fail to boot error problem.

If nothing seems to work, then you need to reinstall macOS Sierra. To reinstall, restart your Mac and press Command + R at startup, then select Reinstall macOS option. For a faster reinstall, create a new bootable drive to clean install macOS Sierra on your MacBook again.

How to recover lost data due to macOS Sierra failure?

If you lost some important data after fixing Mac won't start after Sierra update, you must try professional data recovery software – Remo Recover data recovery tool for Mac to restore all lost data back. It enables you to recover data from failed Mac OS Sierra update or other reasons on all versions of Mac OS with ease. Just download the trial edition of the application for free and let it help you to get lost data.