How to fix "First Aid found corruption that needs to be repaired" error?

By Katrina | Posted to Mac Data Recovery Tips, updated on May 7th, 2020 |

If the error message "First Aid found corruption that needs to be repaired" appears on the screen of your Mac, have no fear. You can solve this error, leaving your Mac and your files safe and secure.

Introduction to the "First Aid found corruption that needs to be repaired" issue

This message is a result of internal software within your Mac having detected corruption. Signs of corruption include various noises, and repeated program crashes. Disk errors, and frequent error messages are also signs, among several other symptoms.

First Aid found corruption that needs to be repaired

There are two occasions in which Mac users may find the error message to appear. One way in which this message may appear is when Mac users attempt to check their startup disk using First Aid. The other way is when a Mac computer will not turn on while a loading bar is frozen on screen. In trying to correct this error, users usually boot into macOS Recovery Mode. As a result, the error message appears when checking the startup disk with First Aid in Recovery.

First Aid can detect and repair damages to partition map, master directory block, and so on. To repair startup volume, you need to run First Aid from Recovery. Running First Aid from Recovery is the best option, but there are others if it fails.

Important: Back up your startup volume

First Aid can be run on a startup drive but cannot repair it until specific measures are taken. Operations on a Mac with a corrupted startup drive may overwrite the original data. As a result, data loss occurs. To prevent the loss of data before running First Aid, you must backup your data. If you do not have your data backed up, data recovery can be used to do so.

To back up data from the corrupted startup drive, you can make use of free Mac hard drive data recovery software - iBoysoft Data Recovery for Mac. It can recover data from unbootable Mac hard disk, recover lost data after macOS update failed, and recover lost data from corrupted or unmountableAPFS boot volume. This software can recover photos, documents, videos, audios, emails and much more on macOS 10.15/10.14/10.13/10.12 and OS X 10.11/10.10/10.9/10.8/10.7.

Tutorial to rescue data from startup disk with iBoysoft Data Recovery for Mac

Tips: If your Mac can't turn on when First Aid found corruption that needs to be repaired, you need to run Mac data recovery from macOS Recovery Mode to get files off.

Step 1: To avoid overwriting the lost files, please download iBoysoft Data Recovery for Mac to an external drive, instead of your startup disk.

Step 2: Double click iBoysoft Data Recovery for Mac installation file, then double click iBoysoft Data Recovery for Mac icon to directly run it (instead of dragging it to Applications folder).

Install iBoysoft Data Recovery

Step 3: After launching iBoysoft Data Recovery for Mac, select the startup disk.

Recover lost data from startup disk

Step 4: Click "Scan" to search for all lost files on the startup disk.

Step 5: Preview the listed recoverable files, choose those we want, and click "Recover" to get them back.

How to fix the corrupted Macintosh HD when First Aid found corruption that needs to be repaired?

After using iBoysoft Data Recovery for Mac software to back up the files, you should work to resolve the error.

There are several solutions that can solve the error message.

Solution 1: Run First Aid from Recovery

First Aid is a small utility that is designed to verify and fix an array of minor problems of a drive. These problems include data structure repair and hard drives having trouble mounting. Unfortunately, First Aid can fail, resulting in the need to run First Aid from Recovery Mode.

To repair the startup volume, run First Aid from recovery

Recovery Mode loads tools that help in completing various actions. These actions include reinstalling macOS, and erasing a hard disk, among others. In recovery, you want to be sure to mount the startup disk before running First Aid. To repair the startup volume, run First Aid from Recovery. If you find that your startup disk is encrypted, be sure to mount and decrypt it first using your password. Wondering how to run First Aid from Recovery?

Follow the steps below:

Step 1: Turn your Mac computer on and immediately press-hold Command + R.

Step 2: Once the Apple logo, a spinning globe, or another startup screen appears, release the keys.

Step 3: You may be prompted to enter a password. Enter the requested password and continue.

Step 4: The macOS Utilities window should appear. This means that startup is complete.

Step 5: Once you start up from macOS Recovery, select Disk Utility from four utilities and then continue.

  • Restore from Time Machine Backup: (restore your Mac from a Time Machine backup)
  • Reinstall macOS: (download and reinstall the Mac operating system)
  • Get Help Online: (browse the web using Safari to find help for your Mac. Links to Apple's support website are also included. Please note though that browser plug-ins and extensions are disabled)
  • Disk Utility: (used to repair your disk, erase your disk, or other storage)

Step 6: Select the startup disk and click on First Aid to run this utility.

To quit macOS Recovery, choose to either restart or shut down from the Apple menu (apple logo). If you wish to choose a different startup disk before quitting, chose Startup Disk from the Apple menu.

Running First Aid from Recovery is the easiest way to repair your corrupted Mac hard drive. However,this solution is not always successful. If this is the case, another possible solution is to run First Aid from Internet Recovery.

Solution 2: Run First Aid from Internet Recovery

You may find when trying to resolve the problem that your Mac cannot boot into macOS Recovery mode. This is because the Recovery partition within your computer has taken damage. If this is the case, you will need to run First Aid from Internet Recovery. The steps to run First Aid from Recovery are below:

Step 1: Press-hold Command+ Option+ R or Command + Option + Shift+ R. By completing one of these actions your Mac will boot into Internet Recovery.

Step 2: Once the Apple logo, a spinning globe, or another startup screen appears, release the keys.

Boot into internet recovery mode when First Aid found corruption that needs to be repaired

Step 3: Then choose Disk Utility and run First Aid.

This solution is of great use if your computer cannot boot into macOS Recovery mode. By running First Aid from Internet Recovery, you can save yourself from having to attempt much riskier solutions.

Solution 3: Back up files and Erase the Startup disk from Recovery Mode

If you are unable to run First Aid from Recovery Mode when trying to resolve the "First Aid found corruption that needs to be repaired" error, this is because Disk Utility can't repair the startup disk. As a result, you must erase the startup disk from Recovery Mode. It is important that you rescue your files from the corrupted startup disk first though. Doing so can keep you from losing data.

Once recovering your files, you need to erase your Mac hard drive and then reinstall macOS. The steps to do so are below:

How to erase Mac startup disk from Recovery Mode?

Step 1: Start your computer from macOS Recovery by Command + R.

Step 2: Once on the macOS Utilities menu, select Disk Utility, and then click continue.

Step 3: Be sure that the sidebar in Disk Utility shows the name of your startup disk. Unless renamed, the volume representing your startup disk should be "Macintosh HD".

Step 4: You can then select Macintosh HD in the sidebar.

Step 5: Click the Erase button/tab and then complete the following actions:

  1. Name: enter the name in which you wish the volume to have after you erase it. An example name would be "Macintosh HD".
  2. Format: To format a Mac volume, choose either APFS or Mac OS Extended (Journaled). Usually, Disk Utility shows the recommended Mac format by default.

Step 6: After choosing your name and format, click Erase to begin erasing your hard drive. Please note that you may be to enter your Apple ID.

Step 7: Once everything has been erased, quit Disk Utility to return to the Utilities window.

This solution is intense but can be effective in repairing your corrupted drive. Also, it is important to note that this solution is not necessary, unless your startup disk is damaged.

To start up your Mac from this volume again, choose Reinstall macOS from the Utilities window. Then, continue on.

How to reinstall macOS from Recovery Mode?

The steps to reinstall macOS are below:

Step 1: Restart your Mac by clicking on the Apple logo in the upper left corner of your screen and clicking "Restart". As your Mac restarts, move into Recovery Mode by press-holding Command + R.

Step 2: There will be four options appear on the Utility Menu on your Mac screen. These options include: Disk Utility and Reinstall macOS, among others. Select Reinstall macOS from the Utility Menu. Afterwards, click continue.

Reinstall macOS or Mac OS X when First Aid found corruption that needs to be repaired

Reinstalling macOS should be your last effort in attempting to repair your drive. If you did have to do so though, you should find that your hard drive has been repaired.

Summary

The "First Aid found corruption that needs to be repaired" error message can be intimidating. While intimidating, it can be resolved. Your options to do solve it are running First Aid from Recovery on Mac or by reinstalling macOS. By doing so, your Mac hard drive should be running in no time!