A corrupted hard drive on a Mac can cause your heart to start racing fast. You might wonder:

“Can I fix this problem?”

“Will I get the chance to access my files again?”

how to fix a corrupted external hard drive mac

If you can recognize the symptoms of a corrupt Mac hard drive early, it is usually possible to repair the problem. When fixing it isn’t possible, you have a better chance to grab your folders and files.

What Are the Symptoms of a Corrupt Mac Hard Drive?

Your Mac starts acting strange when you have a corrupt hard drive. The symptoms might seem random at first, but you’ll see problems continue to increase.

  • You have applications that unexpectedly quit.
  • Your computer stops responding to input.
  • When you attempt to open files, some won’t respond.
  • The system won’t transfer files to new folders.
  • In severe situations, your Mac might refuse to start.

How to Fix a Corrupted Hard Drive on a Mac

If you know for sure that you have a corrupted hard drive on a Mac, you can take these steps to restore access or recover your information.

1. Repair the Corrupted Hard Drive Using Disk Utility

You can use Disk Utility to repair a corrupted hard drive in some instances. This is not a guaranteed fix, but it’s worth trying before moving on to other potential solutions. To do this, follow these steps:

  1. Launch Terminal
  2. Type the following: diskutil repairVolume /Volumes/X, replacing X with the drive name
  3. Press Enter
  4. Disk Utility will now attempt to repair your disk – wait for the process to finish
  5. Check the results – the tool will inform you if the operation was successful or not
  6. If it succeeded, try accessing the disk again

2. Initiate the FSCK Command

Knowing how to check if an external drive is corrupted on Mac or if your internal HDD has this issue follows a similar process.

Users with older Macs that don’t have a T2 chip can reboot the Mac into single-user mode by holding the Command + S combination to repair a corrupt partition that limits access.

  1. Open Terminal. You’ll type this command:
    diskutil list
  2. Press Enter. The computer will give you a corrupt partition number.recover data from corrupted external hard drive mac
  3. Restart the Mac to enter single-user mode.
  4. Type this command:
    /sbin/fsck_hfs -fy /dev/[partition number]

  5. Press Enter. The Terminal will scan for errors and repair the ones it finds.how to check if external drive is corrupted mac
  6. If your Mac says that the file system was modified, the FSCK command found and repaired the issue.
  7. Run the command a second time. When the Mac says that the volume appears to be OK, type reboot. You’ll restart the computer to reach the login screen.

If your machine has a T2 or M1 chip, follow these steps based on the chip manufacturer.

T2 Recovery Mode
If you have an Intel chip (T2), start your Mac in Recovery Mode by pressing Command-R during a restart and then proceed to the common steps.

M1 Recovery Mode
Apple Silicon (M1) users should proceed next steps:

  1. Select Shut Down from the Apple menu.
  2. Press and hold the power button until the Loading startup options message is displayed.
  3. Click Options and then Continue. Enter administrator credentials if prompted. Proceed to the common steps.

Common steps for Macs with T2 steps:

  1. Open Disk Utility.repair corrupted external hard drive mac
  2. Select the normal boot volume and mount it using the Mount command if necessary.mac os recover files from a corrupted drive
  3. Close Disk Utility and switch to Terminal.how to fix corrupted hard drive mac
  4. Run your desired commands in Terminal for example
    diskutil repairVolume /Volumes/[Drive Name].fix corrupted hard drive mac recovery mode

3. Try Free Software to Recover Mac Hard Drive Data

There are many free and paid software solutions that can help you to recover data from corrupted hard drives.

While they won’t help you address the actual cause of data corruption, these tools are capable of telling apart recoverable files from corrupted data and transferring them to an external drive. That’s why we recommend them to users whose top priority is to regain access to important data.

Free data recovery software works reasonably well when dealing with less serious cases of data loss, but its limitations start to show when tacking more complicated data loss scenarios. If you need to recover important files, you should increase your recovery chances by using freemium software such as Disk Drill for Mac, which lets you preview all recoverable files for free. 

  1. Download and install the free version of Disk Drill’s software.
  2. Launch the recovery software on Mac.
  3. Select your drive and click on the “Search for lost data” button.Click on the Search for lost data button for scan your hard drive
  4. Preview the results through the scanning effort to make sure they are recoverable.preview files from your corrupted hard drive
  5. You can then select all files you want to recover and click the Recover button to get them back.

4. Recover from a Time Machine backup drive.

If you use Time Machine on Mac, you can revert to a previous version to eliminate the corrupted files. This method works if you have a saved disk image that doesn’t contain the problem.

Here’s what you need to do:

  1. Connect your Time Machine backup disk if it’s not already connected to your Mac.
  2. Open the folder that contained the deleted files. For example, if the files were in your Documents folder, open Finder and select Documents from the sidebar on the left.
  3. Click the Time Machine icon located in the Menu Bar and choose Enter Time Machine.Emptied Trash on Mac Enter Time Machine
  4. Locate the files you want to recover using the timeline on the right edge of the screen.
  5. Click Restore to restore the selected file. Time Machine

5. Hire a hard drive recovery service for Mac.

If you fail to fix your corrupted hard drive at home, you can always hire a hard drive recovery service and let experienced professionals with state-of-the-art equipment recover your data for you. Professional data recovery services are often more costly than products like Disk Drill, but they can help you get to the missing data when other methods don’t work.

6. Try Connecting the Drive to Another Computer

It’s possible that the fault is not in the disk drive, but in your Mac itself. To verify this, you can try connecting the disk to another computer. Simply do this:

  1. Unplug the drive from your Mac
  2. Plug it into another computer – you can use a PC or a Mac
  3. Check if the drive is accessible

If that works, it indicates that there’s an issue with your Mac. You might have to send your computer for a repair to address that.

7. Connect the Drive Directly (Instead of Using a USB Hub)

If you’re using a USB hub, that’s another potential source of failure. You may be dealing with a faulty USB hub, while the drive itself is fine, and so is your Mac. Simply unplug the drive from the USB hub you’re using, and try connecting it to a USB port on your Mac directly.

If that doesn’t work, try switching to a different USB port. If one of those two fixes work, you’re likely dealing with a damaged USB hub or USB port on your Mac. Try replacing your USB hub with a different one and see if that fixes the issue.

8. Check Your Finder Settings

There’s a setting in Finder which can make external drives invisible. You may have this setting enabled without realizing it, which could lead you to believe that your drive is corrupted. To check if that’s the issue, try these steps:

  1. Launch Finder
  2. Go to Finder -> Preferences
  3. From the list of checkboxes under “Show these items on the desktop:”, make sure External disks is checkedshow external disks on desktop mac
  4. Close Finder and reopen it
  5. Check to see if your disk shows up now

If that fixes your issue, it means the drive was not damaged in the first place.

9. Reboot in Safe Mode

Safe Mode can allow you to boot your computer with minimal extra software and utilities, and is a great way to troubleshoot various issues. It can also help you access a corrupted hard drive in some cases. Simply do the following:

If you have an Intel chip:

  1. Turn off your Mac
  2. Wait for 10 seconds
  3. Turn on the Mac and keep the Shift key pressed through the boot-up sequence

If you have an Apple chip:

  1. Turn off your Mac
  2. Wait for 10 seconds
  3. Turn on the Mac and keep the power button pressed
  4. Choose the right startup disk

Hold down Shift, and click on Continue in safe mode

How to Prevent Hard Drive Corruption on macOS?

The best way to prevent a “macOS recover files from a corrupted drive” problem is to monitor your system’s health frequently.

You can take these additional steps to ensure your Mac doesn’t encounter hard drive corruption problems in the future.

🔌 Shut Down Your Mac Safely

When it is time to turn your Mac off for the day, go to the Apple menu at the top left to initiate the command. If you need the computer to sleep, you’ll find that option available in the same location.

You don’t want to press and hold the power button to accomplish this result unless you have no other choice.

⚡ Prevent Spills and Exposure

Your Mac can handle a lot, but it doesn’t like liquids. If you must drink something by your computer, keep it in a closed container with a spill-proof lid.

It would be best if you also avoid extreme heat or cold when storing your Mac.

Some problems occur because food or dust gets into the drive mechanism. If you maintain a clean working area, most issues get proactively solved.

📉 Monitor Your Storage Drive

When something doesn’t seem right, you can run First Aid on your Mac. This command checks the disk for errors and repairs them if any get found. Disk Drill gives you the capability to monitor S.M.A.R.T. drive status on older Macs. To activate this feature, turn on S.M.A.R.T. monitoring in preferences and select the drive you want to monitor. An icon will be displayed in your Mac’s menu bar.

💽 Back-Up the Storage Drive

Whether you use Time Machine or a third-party tool to create an image of your drive, it is critical to keep at least one copy of your files and folders. If something happens, you can use this compressed storage medium to restore your Mac.

In Conclusion: Fixing a Corrupted Hard Drive on a Mac

Although a corrupted hard drive on a Mac can get your adrenaline flowing, it is possible to retrieve files and restore the disk.

When you bookmark this guide, you’ll have a resource that lets you access the steps you need to correct your problem.

Software tools like Disk Drill for Mac are useful when First Aid and Time Machine won’t work or are unavailable. You can also use third-party free tools to get the results you want.

A corrupted drive won’t fix itself. If you take these steps today, you can get your Mac running better faster than you might realize.


Robert Agar

Robert Agar, a dedicated data recovery writer, has been a pivotal part of the CleverFiles team for over 6 years. Before this, he enriched IBM for 13 years as a Backup and Recovery: TSM Subject Matter Expert. A proud alumn...

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Approved by
Brett Johnson

This article has been approved by Brett Johnson, Data Recovery Engineer at ACE Data Recovery. Brett has a Bachelor's Degree in Computer Systems and Network, 12 years of experience.