But as is the case with each Mac operating system update, some users will painfully encounter a slew of problems/issues, like download error, Mac compatibility issue, macOS Sierra upgrade failed, install stuck, slow Mac performance etc. This list of macOS Sierra problems and solutions will show you how to fix the most common problems with. MacOS Sierra won't start up after update. After successfully installing macOS Sierra without problems, some users get stuck at the reboot: macOS Sierra issues with first boot up. Some MacBook/iMac get a white screen with an Apple logo, while some other boots get stuck on black screen.
MacOS Sierra has now been updated into 10.12.2 version and many Mac users are trying to get developer's beta version for their Mac devices so to get latest new features. However, some users complain that their Mac computers stops working after installing new macOS Sierra. The exact problem is that macOS Sierra won't boot after update. If you are having the same problem that your Mac fails to boot after updating macOS Sierra, don't worry. Effective methods are available here to help you fix macOS Sierra won't boot error without losing any data on your Mac now. Now let's see how to fix macOS Sierra won't boot or fail to start up after the update. Force to boot Mac to fix macOS Sierra fail to boot error.
Press and hold Power button for a few seconds till Mac turn off;. Wait a few seconds and press Power button to turn on Mac. If this doesn't work, you may need to try other 4 methods here in this article. Try Safe Boot Mac from Safe Mode to fix macOS Sierra won't boot error. Turn on Mac, press Shift when you hear the startup sound and release it till you see Apple logo;. After Mac fully starts, restart the computer normally without holding any keys/buttons.
Wait patiently till Mac computer finish the reboot process. Use Disk Utility and restore from Recover Mode to fix macOS Sierra fail to boot error. Boot Mac up, press Command + R during the boot-up process;. Click Disk Utility option Click First Aid and try repairing Mac's disk;.
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Disk Utility will automatically run a fsck (file system check) operation to help you repair macOS Sierra fail to boot error;. If this fails, try to restore from Recovery mode. Reinstall OS X in Recovery Mode will automatically download and install the latest macOS Sierra for your Mac device. Use Terminal to fix macOS won't boot error after update. Open Terminal Applications Utilities;. Enter: systemprofiler SPExtensionsDataType /Desktop/kextList.txt and hit return;.
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Open the kextList.txt file on desktop Press Apple(Command) + F to bring up find;. In the find field insert ' Obtained from: Not Signed' and copy the destination to the.
Kext file to a list for use later;. Click Next to cycle through all of them, for example: /System/Library/Extensions/JMicronATA.kext. Browse your drive to /System/Library/Extensions and remove all unsigned kext files;. Reboot and your Mac boot problem shall be all set. Reinstall macOS Sierra to fix boot error after update The last method to fix macOS Sierra fails to boot after update error is to reinstall macOS Sierra. You can download wanted macOS Sierra and create the new bootable drive to clean install macOS Sierra on your computer again. Then macOS Sierra fails to boot or cannot start up after update error will be thoroughly solved.
Extra tip: Restore lost data due to macOS Sierra failure. In order to avoid unexpected data loss trouble due to macOS Sierra update, or if you have lost some data after fixing macOS Sierra won't boot after the update, you can try to restore backups from Time Machine.
But if you don't have any backups, you may try professional Mac data recovery software - to get all lost Mac data back. It allows you to restore all lost data due to macOS update or other reasons within 3 steps. Just download it and let it help get all lost data backup now: Step 1.
Where was data lost after operating system update? Choose the location and click Scan. EaseUS Data Recovery Wizard for Mac will immediately scan your selected disk volume and display the scanning results on the left pane.
After the scan, select the target files that were unknowingly lost during or after the update and click Recover Now button to get them all back.