USB drives are great for providing additional storage for your Mac or MacBook. Many people use them to share music or photo libraries with friends. But like all disk-based storage devices, it can suffer data loss or corruption. You may need to fix a corrupted USB drive on Mac or fix a broken USB device while saving its data.

how to fix a corrupted usb flash drive

We are going to show you how to retrieve files from a corrupted USB drive with your Mac. We will also look at things like how to format a corrupted USB drive on a Mac. Let’s get started.

Signs of a Corrupted USB Drive on a Mac

How do you know if your USB drive has been corrupted? Before looking at the signs that your USB drive is corrupted, let’s look at how to figure out if your USB port is broken on a MacBook or Mac computer.

If your computer has more than one USB port, your first course of action should be to connect a USB device that is having issues to a different port. If that is not an option, try connecting the device to another computer’s USB port. In this way, you can determine if the drive is fine but the interface is the problem.

There are multiple signs that you may have a bad drive that requires you to recover corrupted files from USB on your Mac. Here are some of the most common indicators of a corrupted USB drive.

  • The USB drive is not recognized by the OS and does not appear in Finder.
  • The drive is visible in Finder but you cannot see or access its files and folders.
  • Files are arbitrarily renamed and cannot be opened.
  • The drive appears grayed-out in Disk Utility.
  • You encounter macOS error messages when attempting to access the drive.

If you are experiencing any of these issues, you may have a corrupted USB drive. Let’s look at how to recover USB files from a corrupted drive on a Mac and show you some methods that may get your data back.

❗️If you suspect your USB drive is corrupted, stop using it immediately. Any attempt to write new data to the drive can further corrupt its contents and make it impossible to recover files with data recovery software. Don’t use the device again until the issue has been fixed or the data has been recovered.

How to Recover a Corrupted USB on Mac with/without Data Loss

Multiple methods are available with which to attempt to recover corrupted files from a USB device on a Mac. Some involve destroying the data stored on the drive so it can be reused and others recover the data from the corrupted device.

Let’s investigate these methods and see if one of them can help you in getting data off a corrupted USB drive.

Solution 1: Fix a Corrupted USB on a Mac With Disk Utility

Disk Utility is an application that is installed with macOS. By default, it should be located in the Other folder in Launchpad. The following steps show you how to fix a corrupted USB flash drive on Mac with Disk Utility.

  1. Open Disk Utility and choose View > Show All Devices.
  2. Select the USB drive from the sidebar and click the First Aid button. fix USB with disk utility Mac first aid
  3. Click Run in the First Aid dialog and follow the onscreen instructions.
    run First Aid on Mac to fix USB Drive
  4. Click Done when the First Aid process finishes.

The USB drive should be recognizable by your Mac if Disk Utility is successful. You should be able to access the data on the drive at this point. If not, you may want to try data recovery software which is discussed in a later section of this article.

If Disk Utility is not successful in fixing the drive, proceed to the next method.

Solution 2. Repair the USB Drive With Terminal on Mac

You can also use Terminal to fix your corrupt USB drive. This method offers slightly more control over the whole process compared to when using Disk Utility for this job. But if you’re not comfortable with using Terminal commands, it’s best for you to choose the previous solution.

Before you start repairing your flash drive with this method, it is important to note that this process will erase all of the data from your device.

The following steps show you how to fix a corrupt USB drive on Mac via Terminal.

  1. Connect the USB drive to your Mac.
  2. Head to Launchpad and use the search field at the top to find the Terminal application. Once you’ve found the app, click it to open.
  3. In the window, type in diskutil list and hit Return. You’ll view a list of all of the internal and external disks connected to your Mac.
    view disks via Terminal on Mac
  4. Copy and paste diskutil verifyDisk /dev/disk2 (replace 2 with the corresponding disk number) to verify your flash drive. Hit Return.
  5. If you get an error saying GPT partitioning scheme is required, type in diskutil eraseDisk JHFS+ BackupMaster disk2 to format the drive and hit Return. Then repeat the previous command.how to fix USB Drive on Mac via Terminal
  6. Copy and paste diskutil repairDisk /dev/disk2 and hit Return to start the repair process.
  7. You’ll be warned that this action may erase your USB drive. Type y and hit Return to move forward.how to repair USB disk on Terminal Mac
  8. Once you see Finished partition map repair on disk2, you can quit Terminal and eject your flash drive.

If Terminal didn’t fix the issue with your USB drive, you should give the next solution a try.

Solution 3: Update the USB Driver

The USB device driver is updated automatically through macOS software updates. Follow these steps to see if there are any updates currently available for your Mac and manually install them.

  1. Choose About This Mac from the Apple menu.
  2. Click on Software Update to check for updates.Update the USB Driver
  3. Click the Update Now button if updates are available. You can click on More info to see details about the update

If there were any USB driver updates, they will now be installed. Try to access the USB drive again to see if the update resolved the problem.

Solution 4. Check If the USB Device Is Encrypted or Has No File System

Maybe there’s nothing wrong with your flash drive? There is a chance that you can’t access the files located on the device because it’s encrypted (password protected).

You won’t be able to access the data from an encrypted USB drive on Mac without knowing the password.

password encrypted USB Drive on Mac

However, if you want to make such a drive usable again, then you can use Disk Utility to reformat the drive (check out Solution 5 for more information). But keep in mind that this will erase all of the data stored there.

Another possible reason for you not being able to access the data from your USB drive is because the drive uses a file system that isn’t supported by your Mac. Not all file systems are compatible with macOS (for example, ext3), which means if your flash drive has such a format, you won’t be able to use it on your Mac.

To check your flash drive file system type, do the following:

  1. Launch Finder.
  2. Find the USB drive on the sidebar. Press the Control key and click the drive for a drop-down menu to appear.
  3. Click Get Info.how to check usb file system Mac
  4. Next to Format, you’ll see the file system type used by the USB drive.

The file systems supported by macOS are APFS, Mac OS Extended, MS-DOS (FAT), and exFAT. So if the USB drive uses a different file system, you should reformat the drive and choose a file system for the drive that is supported by the Mac operating system.

Solution 5: Fix an Unreadable or Broken USB Flash Drive by Reformatting

Before attempting this method of fixing a broken USB stick on a Mac, be advised that it may result in the loss of any information residing on the drive. You may be able to recover data with recovery software after formatting, but it is better to try the recovery before you format the USB drive. The following steps show you how to fix a USB flash drive by reformatting it on your Mac.

  1. Connect the USB drive to your computer.
  2. Launch Disk Utility.
  3. Select the USB drive from the list in the left panel.
  4. Choose Erase. Do not select extra security options if you plan to try and recover data from the device.Fix an Unreadable or Broken USB Flash Drive by Reformatting
  5. Name the drive and select the format you want to use.
  6. Click Erase in the bottom left corner.
  7. A progress bar will open and display the status of the procedure.
  8. Click Done when Disk Utility is finished formatting the corrupted USB.formatting flash drive on Mac

A normal format may allow you to recover data with recovery software as outlined in the next section. Formatting with multiple passes will fully clear the storage space and make it impossible to recover any data from the USB drive. Formatting the disk is a method of permanently fixing a broken USB device.

Solution 6: Recover a Corrupted USB on Mac with Data Recovery Software

Mac data recovery software can retrieve data from a corrupt or formatted USB drive. The key is that the drive must be recognized by the operating system for the recovery application to work on it.

To recover files from a corrupted USB drive on your Mac:

  1. Download and install Disk Drill USB Recovery Software for Mac.
    Disk Drill
    Data recovery for free
    Your Companion for Deleted Files Recovery
  2. Connect the USB device to your Mac computer and launch Disk Drill.
  3. Select the USB flash drive from the app’s disk list.select USB Drive on Mac disk drill
  4. Click the Search for lost data button to start scanning for deleted files.
  5. If you want to preview the recoverable files while the app is still scanning your flash drive, click Review found items.review found items on usb disk drill Mac
  6. Choose the files you want to restore and click the Recover button.choose files to recover disk drill Mac USB Drive
  7. Select a safe location to save the recovered data and click OK.
    choose where to save recovered files Mac disk drill

Disk Drill makes data recovery easy with this simple procedure. Be sure not to save the recovered files to the affected USB drive to avoid overwriting the data before it can be retrieved.

Why does this work? The answer is that deleted data is often still physically present on the storage device. The logical links that make the data accessible by users and applications have been removed. Data recovery software repairs these links and makes deleted files and folders accessible again. The recovery might seem like magic, but it’s the result of sophisticated scanning algorithms.

Solution 7: Send the Device to a Data Recovery Service

getting data off a broken mac with usb

If all else fails and the information on the corrupted or damaged USB drive is important, you may want to engage a data recovery service to attempt the recovery. The technicians at a data recovery center use specialized software and hardware tools to clone the storage device and extract its data. Here’s how you go about using a data recovery service to get back your valuable information.

  1. Contact the data recovery center to obtain shipping information and receive a preliminary estimate on the potential data restoration.
  2. Ship the device to the recovery center.
  3. Upon receipt, the data recovery center will examine the device and provide a more realistic estimate for performing the recovery.
  4. Technicians will extract the data from the device and ship it to you on new media.

A data recovery service is the most expensive option for recovering your data, but may be necessary if other options do not work. Choose a reliable service like CleverFiles Recovery Center. A trustworthy recovery center will not charge you unless they can restore your data and will not advertise a per-gigabyte recovery price.

How to Prevent USB Drives on a Mac From Becoming Corrupted

Here are some tips that may help you minimize the chances of a USB drive becoming corrupted.

  • Take care when connecting and disconnecting the device to avoid damaging the connectors.
  • Make sure you run antivirus software and limit the exposure of the device to strange computers whose safety cannot be verified.
  • Don’t remove a USB drive without ejecting it from your computer.
  • Allow all read and write operations to complete before removing the drive from a computer or other device.

Conclusion

All hope is not lost if you are faced with a corrupted USB drive. You may be able to fix a corrupted USB drive on Mac using the features of the operating system. You can also recover data from a corrupted USB drive using data recovery software like Disk Drill.

Follow our advice and don’t use the USB drive until you have attempted data recovery or you risk further corruption that will make it impossible to save your information.

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Romana Levko

Romana Levko is a content writer with a strong interest in the technology field: data recovery, cybersecurity, and everything Apple are among her favorite subjects to explore. Her goal is to expand the reader’s unders...

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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.