How to Repair External Hard Drive on Mac (2024)

This article will describe how to repair an external hard drive on Mac that won't read or mount properly. Here we offer 7 ways to fix the problem. Use EaseUS Data Recovery Wizard for Mac to recover data from this external hard drive while protecting files.

Table of Contents

Finding the finest external hard drive for Mac is essential because it prevents you from overloading your Mac computer with enormous data that slow it down. Alternatively, you can move everything from your Mac to an external storage device so that you can access anything from anywhere at any time.

Left a download from google drive into my HD overnight as the file was pretty big and the next morning i found that the download had been disrupted. Had to remove the HD as finder was unresponsive. Now I am unable to reconnect the HD or access the files on my macbook. The drive is still recognized, the space is still being occupied, but no files are visible. In addition, finder and disk utility will freeze/hang when I try to do anything more with it. Is this a problem with the downloads or the hard drive? It was working fine previously before I initiated this particular download.

from Apple Community

However, the issue then could be if you unintentionally remove files from your external hard disk. Worsely, you need to repair external hard drive on Mac if the files on your external hard drive get corrupted.

First-Aid: Recover Lost Data from External Hard Drives on Mac

In this article, we prepare seven options for repairing an external hard drive on Mac, while some techniques, such as using a Mac Terminal, risk data loss. To save the data from your corrupted external hard drive and prevent further data loss, we highly advise you to recover data from your Mac external hard drive first.

Don't worry if you can't view or see every piece of saved data on the hard drive. You may easily recover your lost data from the drive by using EaseUS Data Recovery Wizard for Mac, which can easily retrieve data from inaccessible HDDs, USB flash drives, SD memory cards, and other storage devices.

  • It can recover partition Mac from the PC or the Mac's original internal/external hard drive.
  • It supports various device types, so you may recover data from deleted or formatted disks on a Mac, SSD, or HDD.
  • It supports hard drive data recovery for sudden deletion, formatting, hardware corruption, virus attack, and system crash.

Install the EaseUS data recovery software, and follow the 3-step guideline to get the data back from the corrupted external hard drive on Mac.

Step 1. Correctly connect your external hard drive to your Mac. Launch EaseUS Data Recovery Wizard for Mac, and select the external hard drive. Then, click "Search for lost files" to find lost/deleted files on your external HDD.

Note: Before data recovery, you'd better click "Disk Backup" from the left sidebar to create a backup of your external hard drive to avoid further data loss. After backing up the external hard drive, the software can recover data from your external hard drive's backup, and you can remove the external hard drive and use it again.

Launch EaseUS Data Recovery Wizard for Mac

Step 2. After the scan, all file types will be presented in the left panel. Select the file type to find the wanted files on your Mac's external hard drive.

find the wanted files

Step 3. Click the file to preview it. Then, select the files you want to recover and click the "Recover" button. You can save your data to local and cloud drives on Mac.


How to Repair External Hard Drive on Mac (7 Ways)

After rescuing your data from the external hard drive, you can learn 7 methods for resolving failed external hard drives on Mac in this section, and if it is possible for you to have a try, one of them will be the solution to the issue.

🍎Reboot Your Mac in Safe Mode This method involves restarting your Mac in Safe Mode, which helps identify and potentially fix issues by only loading necessary software and drivers. 
🪄Repair External HDD Mac Terminal You can run disk repair commands to fix errors on the external hard drive. This method requires some knowledge of command-line interfaces.
📂Use FSCK Command to Fix the Issue The FSCK command is a powerful tool for fixing disk issues. However, it requires advanced technical knowledge and should be used cautiously to avoid data loss.
🖲️Check the USB Connections on Mac This is an essential troubleshooting step but can often resolve issues caused by loose connections or faulty USB ports. It is simple and non-destructive.
🎚️Try Disk Utility First Aid repair a Mac disk with Disk Utility is a user-friendly method that can resolve many disk-related problems. It is recommended for users with little technical knowledge.
🧹Format Mac's External Hard Drive Formatting should be considered as a last resort, as it permanently deletes all data on the external hard drive. It can effectively resolve significant issues and start fresh.
🔎Check Mac Finder Settings This method is simple and can quickly fix the problem of the external hard drive not appearing in Finder. However, it may not address other underlying disk issues.

Fix 1. Reboot Your Mac in Safe Mode

You can start your computer in Mac Safe Mode, an excellent approach to diagnosing various issues requiring little additional software or services. In rare circumstances, it can assist you in accessing and repairing a corrupted hard drive on Mac.

When you boot your Mac in Safe Mode, several checks are made to stop some software from launching or opening automatically. Safe Mode startup on a Mac will result in the following:

  • Fix problems with the Mac startup disk.
  • Only load necessary kernel extensions.
  • System and font caches should be automatically cleared.

Just carry out the following:

For Intel-based Mac:

Step 1. Shut down the Mac for 10 seconds.

Step 2. Press the Shift key until the Apple logo appears.

Step 3. When the login window displays, release the key.

Apple logo samfe mode

For Apple-silicon Mac:

Step 1. Turn off the Mac for 10 seconds.

Step 2. Turn it on and keep holding the power button.

Step 3. Select the right startup disk.

Step 4. Press the Shift key and click "Continue" to log in to the Mac Safe Mode.

M1 chip safe mode

If the connection between your Mac and the external hard drive is lost, your macOS can't recognize or show up the hard drive. Here is a video tutorial which provides you with more details on repairing an external hard drive Mac.

  1. 00:00 - Introduction
  2. 00:15 - Finder Settings
  3. 00:36 - Disk Utility
  4. 00:56 - Disable Content Restrictions
  5. 01:19 - macOS Software Update
  6. 01:41 - Fix Hardware Issues

Fix 2. Repair External Hard Drive on Mac Terminal

One of the most effective ways to fix your external hard drive is with Mac Terminal. This manual is meant for experienced users who are familiar with the Terminal and command line, though. It is preferable for the majority of Mac users to repair external hard drives directly with First Aid. because command lines are so difficult for regular people to understand.

Step 1. Open Terminal on Mac.

Step 2. Input cd /Volumes and Is. Press "Enter". A list of all the drives will be displayed.

Step 3. Select the problematic external hard disk at this point.

Step 4. Press "Enter" after entering the command diskutil verifyVolume xxx (external storage name).

Step 5. Enter diskutil repairvolume /Volumes/xxx (external hard drive name).

The external hard disk should be fixed after this.

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Fix 3. Use FSCK Command to Fix the Issue

The technique for determining whether your internal HDD has this problem or if your external drive on a Mac is corrupted is the same.

Step 1. Launch Terminal from Applications > Utilities > Terminal.

Step 2. Enter the diskutil list to get a list of all connected drives, mounted and unmounted, at the moment. Find the drive identifier for the one you want to and locate it.

Step 3. When your Mac restarts, press down Command and S to enter Mac Single User Mode before the Apple logo appears.

Step 4. White text will briefly scroll by. When it comes to a stop, enter /sbin/fsck -fy.

FSCK command

Step 4. Type /sbin/fsck_hfs -fy /dev/[drive identification] with the actual drive name in the command line. On an external hard disk, FSCK will examine the file system and try to fix any damage it discovers.

Step 4. Enter reboot at the command line when FSCK has finished examining and repairing the file system. After that, the Mac will restart, returning to the standard login screen.

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Fix 4. Check the USB Connections on Mac

Remove any USB hubs or other extensions you may be using, and try connecting the device straight to the computer instead. To check the USB connection:

  • Plug the external device cautiously back into the port after unplugging it.
  • Try using the external hard drive on a different Mac computer or re-inserting it into a different USB port.
  • Reconnect the hard drive to your Mac using a different USB cable.
  • To prevent outdated drivers from making your external hard drive unrecognizable, see whether any software updates are available in your APP Store.


Fix 5. Try Disk Utility First Aid to Repair External HDD on Mac

Sometimes you can fix a corrupted hard drive with Disk Utility on Mac. Before moving on to other potential fixes, it's worth attempting this first, even if it's not a certainty. Follow these steps to accomplish this:

Step 1. Open the "Apple Menu" > "Restart" > Hold the Command + R keys.

Step 2. Select "Disk Utility" > "Continue" > "View" > "Show All Devices".

Disk Utility

Step 3. Click the corrupted external hard drive you desire to repair.

Step 4. Choose "First Aid" > "Run" if you get the "overlapped extent allocation."

Step 5. The Disk Utility on Mac will repair your external hard drive.

If one of the methods helps repair an external hard drive on Mac, share it on Facebook, Twitter, Instagram, and other social media platforms!


Fix 6. Formatting the Mac's External Hard Drive

If the fixes above don't work, try to format the hard disk. However, make sure to back up the files on your external hard drive if you've already used it with a PC. Your drive will be completely empty after formatting.

Step 1. Connect your Mac to an external hard drive. Some external hard drives require an electrical outlet to function.

Step 2. Enter "Disk Utility" in Spotlight Search, then select the first result. All of the internal and external drives that are linked to your Mac will be visible in the Disk Utility software, which will launch when you click this.

Step 3. Select "Show All Devices" under "View" in the window's top-left corner.

Step 4. To format an external hard disk, click it. This is listed under External Hard Drives on the left side of the screen. Choose the disk (the top choice in the external tree) for the best outcome.

erase hard disk

Step 5. Click "Erase" in the option at the top. A brief pop-up window will appear, informing you that doing so will erase all of the drive's data and that it cannot be undone.

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Fix 7. Check Mac Finder Settings

External drives can be made invisible in Finder using a setting. Unknowingly enabling this feature may give you the impression that your drive is damaged. If doing so resolves your problem, it indicates that the drive was not initially damaged. Try these steps to see if that's the problem:

Step 1. Open Finder on Mac.

Step 2. Open Finder and select "Preferences".

Step 3. Make sure External drives is selected in the list of checkboxes under "Show these items on the desktop:"

Step 4. Relaunch Finder after closing it

Step 5. Check to see if your disk appears right away.

Why the External Hard Drive on Mac Needs Repair

There are two kinds of errors on the Mac external hard drive:

💽Physically Harmed Hard Drive

Unfortunately, it can be repaired manually only in a repair shop or company. For instance, hard drive collapse harms the rotating elements; heavy dust destroys the core components in the sealed area, and scratches on a drive's surface.

✔️Logical Errors

As with most hard drive errors, logical mistakes can be repaired. Typically, a sudden power outage occurs when data is being written to the disk, and malware/virus attacks can cause logical errors. Built-in programs on Mac or third-party software can repair this kind of failed external hard drive on Mac.

😨Crash Errors

You can investigate using the report choices given on the left side to look for potential causes, such as a crash, file corruption, or connectivity problems, that are preventing the external hard drive from functioning correctly.

You can identify the causes of HDD corruption like drives shared between different systems, poor connections, unsafe ejection, interruptions during file transfers, hardware malfunction, virus infection, and misoperation when opening the external hard drive on Mac.


These seven methods are how you can repair an external hard drive on Mac. However, the issue is that you might have to give up your data. We offer the best software - EaseUS Data Recovery Wizard for Mac on the market to recover data from your external hard drive on a Mac to assist you with the Mac hard drive issue.

Mac Repair External Hard Drive FAQs

Here are 4 additional questions about repairing external hard drive on Mac. Check here for the answers.

1. How do I fix my iMac's corrupted external hard drive?

Repair a storage device on an iMac with Disk Utility:

  • Select "View" > "Show All Devices" in the Disk Utility software on your iMac.
  • Choose a volume in the sidebar, then click the "First Aid" button.
  • Click "Run" in the First Aid dialogue, then adhere to the prompts on the screen.
  • Click "Done" after the First Aid procedure is finished.

2. How do I recover an unreadable external hard drive on a Mac?

To fix the disk on a Mac, follow the instructions listed below.

  • Select "Go" > "Utilities".
  • Click "Disk Utility" twice.
  • In the left pane, choose the volume where you wish to repair permissions.
  • On the "First Aid" tab, click.
  • Click "Run" to start the disk repair process after choosing the volume you want to install the Adobe application.

3. How did my external hard drive get corrupted?

Data corruption on hard drives can be caused by software bugs, mechanical component problems, or even electrical occurrences. Larger files take up more physical space on a hard drive's platters than smaller files, making serious data corruption more likely with larger files.

4. Why is my external hard drive not showing up in Mac Disk Utility?

If your external hard drive not showing up on Mac in Disk Utility, select "Show All Devices" from the View tab. You should replace the drive if it is physically damaged and still not showing up.

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Updated by Jaden

Jaden is one of the editors of EaseUS who lives and works in Chengdu, China. She focuses on topics concerning PCs and Mac data recovery. Jaden is committed to enhancing professional IT knowledge and writing abilities. She is always keen on new and intelligent products.

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