> How to > Resource > Fix 'the disk you inserted was not readable by this computer' on Mac

Fix 'the disk you inserted was not readable by this computer' on Mac

Updated on May 10, 2018 by Abby Haines to Resource

Summary

Easy and efficient methods to fix 'the disk you inserted was not readable by this computer' error on Mac are offered here. Try them one by one to get access to your external hard drive, SD card, USB flash drive or even an Android devices. Download EaseUS Mac recovery software to help if data recovery is required.

USB says 'the disk you inserted was not readable by this computer' 
"My Sandisk USB flash drive becomes unreadable and inaccessible for unknown reasons. Whenever I plugged it into my MacBook, I get the error message 'the disk you inserted was not readable by this computer.' I have many family pictures and working documents saved on the USB, is there any way to fix the flash drive and get access to my data?"

the disk you inserted was not readable by this computer

Fixes to 'the disk you inserted was not readable by this computer' error 

To open removable storage devices like an external hard drive, SD card, USB flash drive or even an Android phone or tablet, you usually have to insert it into a Windows computer or Mac. But if the system files or the disk is corrupted, error messages will pop up and prevent you access the device and data. In Mac OS X, the error message usually reads 'the disk you inserted was not readable by this computer.' 

Just like what happened in the story mentioned above, many Mac users have a similar experience of this issue and want to find a fix.  Here, our advice about how to solve this problem is:

Step 1. Check the Mac system.

Just plug in a different external hard drive to Mac, if it appears on Finder, it suggests that the problem is related to the external USB devices, not the Mac. 

Step 2. Check the file system format

Check the file system format of the external hard drive, SD card, USB flash drive or other devices. If it is formatted with the NTFS format, then it is not hard to understand why it is unreadable on Mac. To correct it, please convert NTFS to FAT32. 

Disk formatting will erase data for good. It's good to backup the disk in question on Mac in advance with EaseUS Todo Backup for Mac.

Step 3. Verify or repair the unreadable disk, USB or SD card use Disk Utility

1) Choose Go --> Utilities.
2) Double-click Disk Utility.
3) Select the volume in the left pane for which you want to repair permissions.
4) Click the First Aid tab.
5) Select the volume to which you want to install the Adobe application, and then click Repair Disk Permissions.

Step 4. Initialize the disk and recover data

If the problem continues, you have no choice but agree to initialize the disk you inserted as the pop up warns.

Care about important data? Please download and install EaseUS Mac data recovery software on your Mac because this fix will bring data loss on the storage device.  

The overall troubleshooting steps are as follows:

1) Click on the Initialize button.
2) This will open Disk Utility. From the menu bar -> click View -> Show All Devices. You can locate the problematic drive there, which Mac recognizes it as unformatted space.
3) Choose the drive from the left pane and click Frist Aid.
4) Click Repair Disk. Wait for the repair process ends. Can't repair disk because Disk Utility can’t repair this disk? Please continue.

5)Navigate to the Erase button. Name the drive and select File Format and click Erase. This will format your drive with a correct file system.

After this, your Mac should now recognize the disk correctly. You will no longer receive such an unreadable disk error.

To recover formatted data on the disk, open EaseUS Data Recovery Wizard for Mac and follow this article guide: Recover Lost File from Formatted USB Flash Drive on Mac.

recover drive data on mac

If 'the disk you inserted was not readable by this computer' error is still consistent after trying all the methods, we recommend you to backup the drive always. Purchase a new device and be prepared for a drive failure soon.