‘MacOS needs to repair your library to run applications’ fix

A number of MacOS users have upgraded their devices to High Sierra for a number of reasons. Added security, clear photos and fancy features are some of these reasons. Though this sounds a substantial move, the majority are hit by ‘macOS needs to repair your library to run applications’ message just after the update.

The message pops up each time you open an application in your mac. To help you enjoy the Mojave or High Sierra new features, try to fix the macOS library using the following options.

Fixing ‘macOS needs to repair your library to run applications’ error

Follow these steps to fix the macOS needs to repair your library issue:

Solution 1: Run the First Aid Feature

This feature is used to repair disks. You can also use “First Aid” to diagnose your apps when they are not running properly. You can also use it when you get the message “macOS needs to repair your library to run applications after migration.” Follow these steps to run First Aid.

  • Navigate to Finder and select Utilities.
  • Click on Disk Utility then select First Aid.
  • Press ‘Run’ on the first Aid dialogue that comes into view

Wait for this feature to finish the required repair process. Reboot your Mac and check if the applications are running smoothly. If the solution is unable to fix the issue, try the next alternative.

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Solution 2: Fix the Exact Application Producing the Error

If a specific application is producing the error message;

  • Click on ‘Option and Command’ keys to open the application
  • Click on ‘Repair’ to repair the application from the pop-up window that shows up.

Wait for few minutes for the program to repair. Restart your device and check if the issue is resolved.

Solution 3: Use the Terminal

  • Restart your Mac and click “Command + R” key to enter the recovery mode
  • Proceed to utilities and open terminal
  • Click reset password and press “return”
  • Select your system drive which in this case is Macintosh HD/SSD then select your preferred username
  • Press on ‘Reset Home folder Permissions and ACL key’

Once you are done with this procedure, restart your machine and see if the error message is still there. If yes, you should consider reinstalling High sierra.

Solution 4: Reinstall High Sierra

The error might occur as a result of you not having a successful Mojave upgrade. As such, you may consider reinstalling High Sierra following these steps.

  • Restart your Mac and press “Command + R” when the startup sound appears. This will take you to recovery mode.
  • While in the recovery menu, Reinstall Mac OS and press continue.
  • Choose Macintosh HD/SSD which is your Mac hard drive
  • Choose install and follow the prompted procedure to finish the installation process.
NB: Before you initiate this process, ensure you have a backup. Reinstalling will delete the whole data on your Mac.

Any of these four solutions should repair Mojave. If they both fail to fix MacOS library, downgrade to Sierra and check if the problem is resolved.

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