> 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 Jan 15, 2019 by Abby Haines to Resource

Summary

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

'The disk you inserted was not readable by this computer.' 

"My Sandisk USB drive has become unreadable and inaccessible for some reason. Whenever I plug 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 work documents saved on the USB, how can I fix my flash drive and get access to my data?"

the disk you inserted was not readable by this computer

Fixes for 'The disk you inserted was not readable by this computer' error 

When you insert a corrupted removable storage device—like an external hard drive, SD card, USB flash drive, or an Android phone or tablet—into your PC or Mac, error messages will pop up and prevent you from accessing  the device and data. In Mac OS X, the error message usually reads: 'the disk you inserted was not readable by this computer.' 

Our advice to bypass this error is as follows:

Step 1. Determine which device has a problem

Plug a different external storage device into the Mac. If it appears in 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 device. If the file system is NTFS format, then it is not hard to understand why it is unreadable on Mac. To correct it, convert NTFS to FAT32. 

Disk formatting will erase data for good, so you should back up the disk in advance. Do this by using a PC and backing up there, or format and afterwards recover data with EaseUS Data Recovery Wizard for Mac. It is safer to back up than to recover after formatting.

Step 3. Verify or repair permissions on the unreadable disk with 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 to agree to initialize the disk when the pop-up prompts.

Download and install EaseUS Mac data recovery software on your Mac because this fix will bring data loss on the storage device.  

To initialize the disk:

1) Click 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.

3) Choose the drive from the left pane and click First Aid.

4) Click Repair Disk. Wait for the repair process to end.

 Disk Utility can’t repair this disk? If so, refer to this linked article. 

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. All steps in this guide are applicable for external hard drives as well as USB drives.

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.