How to Repair Corrupted USB Flash Drive on Mac?

By Katrina | Posted to Mac Data Recovery Tips, updated on September 30th, 2019 |

Summary: It happens frequently that a USB flash drive becomes corrupted. Before you repair the corrupt USB flash drive, you can recover lost data from this USB drive with iBoysoft Data Recovery for Mac and then fix this USB drive by yourself.

To some extent, the USB flash drive makes it easier to transfer files between different computers because it's portable and removable. However, it is possible that your USB flash drive becomes corrupted since you frequently plug it in and out. If you remove a USB flash drive from a Mac computer port before it is properly unmounted and ejected, it increases the possibility of a corrupted USB external drive on the Mac.

Once your USB flash drive is corrupted, your Mac will be not able to read this disk when you inserted it in. In this situation, you may be eager to know how you can repair this corrupted USB drive on your Mac and access your files on it. This post offers feasible solutions so that you can repair the corrupted USB flash drive on Mac.

Table of contents
1. Why your external USB flash drive is corrupted?
2. How to repair corrupted USB drives on Mac?
3. How to prevent external USB drives from corruption?

Why your external USB flash drive is corrupted?

Indeed, for many users who just regularly use a USB flash drive for file storage and transfer, it's hard to figure out why a USB drive suddenly become corrupted and unreadable on the Mac, just like the user below:

"I have a little 2 GB USB flash drive which has been working for a year and just stopped recently...no idea why. It's really a terrible disaster which is messing up my school life as I have all my school stuff like assignments and such stored on the USB. Is there any way that I can use to repair corrupted the USB flash drive without losing data?"

Therefore, we list some common reasons that could render your USB drive corrupted.

  • Unsafe or abrupt ejection. It's one of the most common causes for disk corruption. Many people abruptly unplug external drives like USB flash drive when files are transferring, while the data is not settled down probably.
  • Virus infection or malware attacks. Possibly, you saved some documents like emails, videos that contain a virus to your USB drive, as a result, the disk is infected and the file system is corrupted.
  • Physical damage. Other hardware damage can also make USB drives corrupted. For example, you might have dropped it accidentally, or the drive was overheated and then stopped working.

After knowing what makes your drive unreadable, you can go head to repair this USB disk.

How to repair corrupted USB drives on Mac?

For physical damage, the only solution you can resort to is to send it to a local repair store for specialists' help. However, if your USB flash drive was corrupted because of logical disk errors, you can try to repair it by yourself indeed. There are two feasible solutions to repair corrupted USB flash drive, let's have a look.

Solution 1: Repair corrupted USB flash drive with Disk Utility

Disk Utility's First Aid is your first choice to repair USB flash drive, pen drive, and other external drives on Mac. It's a built-in disk repair tool to check and verify some minor errors on disks without data loss.

Follow these steps to repair corrupted USB external drive with First Aid.

Step 1: Open the Finder on your Mac and click Go at the upper right of your desktop.

Step 2: Choose Utilities and find Disk Utility to launch.

Step 3: Find and select the corrupted USB flash drive in the left sidebar of Disk Utility.

Step 4: Click First Aid in the top center and click Run to repair this drive.

Solution 2: Recover lost data and reformat the corrupted USB flash drive

If First Aid failed to repair your disk, the file system of this USB flash drive might be seriously damaged. Under this circumstance, the solution to fix this is to reformat this drive and give it a new file system so that your Mac can recognize and read your disk.

However, the thing you should notice is that reformatting will erase your data on this drive totally. That's to say, you are going to lose all your files on this USB drive if you don't have an extra backup of your documents, videos, photos, etc. Thus, a safer way to get this issue fixed is to perform USB drive file recovery on your Mac first, and then go to reformat this drive.

To recover lost data from corrupted USB flash drives, you can try data recovery software like iBoysoft Data Recovery for Mac.

Step 1: Recover lost data from corrupted USB flash drive with iBoysoft Data Recovery for Mac

iBoysoft Data Recovery for Mac is a free USB drive data recovery software for Mac that can recover documents, pictures, audio files, videos, emails from corrupted USB flash drive. Also, it is powerful in recovering data from unreadable, unmountable, formatted USB drives. Except for USB drive file recovery, this program can recover lost data from hard drives, external hard drives, SSDs, SD cards, memory cards, pen drives, etc.

You can use iBoysoft Data Recovery for Mac on macOS 10.15 (Catalina), macOS 10.14 (Mojave), macOS 10.13 (High Sierra), macOS 10.12 (Sierra) and Mac OS X 10.11 (El Capitan), 10.10 (Yosemite), 10.9 (Mavericks), 10.8 (Mountain Lion), 10.7 (Lion).

1. Free download and install iBoysoft Data Recovery for Mac.

2. Connect the corrupted USB flash drive to Mac, and then launch iBoysoft Data Recovery for Mac.

3. Select the corrupted USB flash drive and click "Next" to scan for all lost files.

Recover lost data from corrupted USB flash drive on Mac

4. Preview the scanning results to make sure these files are in good condition.

Preview the scanning results

5. Choose files you want to get back and click "Recover".

6. Save the recovered files to another usable drive and then have a check to ensure all lost files have been successfully recovered.

Step 2: Reformat the corrupted USB flash drive

After you get your files back from this USB drive, then you can feel free to reformat it to fix such disk corruption on your Mac. So check the steps below to reformat a problematic drive.

Guide to reformat external USB flash drive on Mac

This will assign a new file system to this corrupted USB drive so that it can be useable again. However, if reformatting can't repair your disk, you should send it to a local repair store and see if they can help.

How to prevent external USB drives from corruption?

Storage media like USB flash drives, SD cards, etc. are prone to corruption because they are frequently plugged in and out for transferring files between different computers. As you may know, a regular backup is the best way to avoid data loss when a disk drive won't work normally, while a few tips to prevent disk corruption would help you even more.

1. Take care of your disk drive

External USB drives are vulnerable to damage, such as excessive vibration on quick motions, water wash, dropping, etc. So, you'd better always make sure that the drive is in a well-protected position.

2. Always remove your external USB drive with safe ejection

External drives are different from an internal HDD because they need to be plugged in and out many times in their life. When you transfer some files and save it to your USB drive, it is possible that a write process gets delayed even though your computer may indicate that the file transfer was complete. To make sure that all files have been transferred properly, you'd better eject your USB drive safely. It will force any waiting file transfers to complete and then power down the device safe and sound.

3. Use the USB slot properly

Most external drives are connected to a computer with a USB slot that is used for power providing and file transferring. Thus, it should be handled and used appropriately. When removing a USB cable from your Mac, pull it out gently. Do not yank it out or twist it. Moreover, you need to check it for damage, dust and corrosion regularly.

Hope this article can help you repair the corrupted external USB flash drive on Mac and recover lost data from the corrupted drive with ease.