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.
Quick ways to fix the disk you inserted was not readable by this computer:
A faulty drive, a file system incompatibility, a connectivity issue, or a computer malfunction are all possible causes of the "disk not readable" message on a Mac.You can try restarting your computer, reformatting the drive or checking for faults with the Disk Utility application, or testing the USB port and cord with another device to fix this.
When Mac warns you, "The disk you inserted was not readable by this computer", it means that your external hard drive or USB flash drive has a detection issue. The following are common causes why the SD card or USB is not readable on Mac and their corresponding solutions:
| Scenarios | Causes | Solutions |
| 🔨Physical Damage to the Disk | Cracks, bends, debris, or corrosion on the card's metal contacts can prevent it from being recognized. |
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| 🗂️File System Incompatibilities | Macs support APFS/HFS+ and exFAT. Cards formatted as NTFS or other formats may not mount. |
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| 📱Unrecognized Card Reader | The Mac's hardware or drivers may fail to detect the reader due to compatibility issues or faulty connections. |
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| 💻Software Issues with macOS | Bugs in the operating system, outdated drivers, or conflicts with third-party apps can disrupt USB detection. |
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| ⚙️Incorrect Finder Settings | Hidden preferences or disabled options may prevent the USB from appearing in Finder. |
|
My Sandisk SD card becomes unreadable and inaccessible for unknown reasons. 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 working documents saved on a USB drive. Is there a way to repair the flash drive and regain access to my data? From Apple Discussion
You receive the error because the disk you attached was not readable by this computer on a Mac. This can happen when you connect an external hard drive, USB drive, or SD card to your Mac. Many reasons could result in this error. Here is the list of the common reasons.
Now that you have learned about the causes, you can try the solutions below to fix "the disk you attached was not readable by this computer". Including errors that appear as "SSD not readable", "USB stick not readable on Mac", and "external hard drive not showing up".
To open removable storage devices, such as external hard drives, SD cards, USB flash drives, or even Android phones or tablets, you typically need to insert them into a Windows computer or Mac. However, if the system files or the disk is corrupted, error messages will appear, preventing you from accessing the device and its data. In macOS, the error message typically reads, 'The disk you inserted was not readable by this computer.'
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 as follows:
Just plug in a different external hard drive to the Mac. If it appears on Finder, it suggests that the problem is related to the external USB devices, not the Mac.
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, it is not surprising why it is unreadable on a Mac. To correct it, please format USB to fat32 on Mac.
Step 1. Connect the USB flash drive to your Mac computer.
Step 2. Open "Disk Utility".
Step 3. Select your USB flash drive on the sidebar, and choose "Erase".
Step 4. Rename the USB flash drive (optional).
Step 5. Select the format as MS-DOS (FAT) for the Format option, and choose Master Boot Record for the Scheme. Then click "Erase".
However, this way will delete all its contents on the flash drive. You can restore data from the malfunctioning USB flash drive to your Mac or external hard drive before formatting it, provided that you have sufficient storage space on either device.
You should use EaseUS Data Recovery Wizard for Mac, a professional Mac RAW recovery program, to recover data from a corrupted or RAW USB flash drive. The most significant feature of this program is its strong and efficient data recovery capabilities, which complement its speedy data backup features.
The overall troubleshooting steps are as follows:
Step 1. Search for lost files
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 devices.
Step 2. Filter and find lost files
After the scan, all file types will be presented in the left panel. Select the file type to find wanted files on your external devices.
Step 3. Preview and recover
Click the file and 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.
If you find this information helpful, please share it with others on social media to help them overcome this common challenge.
Another way to fix "the disk you attached was not readable by this computer on Mac" is to run First Aid in Disk Utility. Follow the steps below to fix the disk on Mac.
Step 1. Choose "Go" > "Utilities".
Step 2. Double-click "Disk Utility".
Step 3. Select the volume in the left pane where you want to repair permissions.
Step 4. Click the "First Aid" tab.
Step 5. Select the volume to which you want to install the Adobe application, and click "Run" to repair the disk.
If the problem continues, you have no choice but to agree to initialize the disk you inserted, as the pop-up warns. Care about essential data? Download and install EaseUS Mac NTFS Recovery software on your Mac, as this fix may cause data loss on the storage device.
Step 1. Click on the "Initialize" button.
Step 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 an unformatted space.
Step 3. Choose the drive from the left pane and click "Frist Aid".
Step 4. Click "Repair Disk". Wait until the repair process ends. Can't repair disk because Disk Utility can't repair this disk? Please continue.
Step 5. Navigate to the "Erase" button. Name the drive, select "File Format", and click "Erase". This will format your drive with the correct file system.
After this, your Mac should now recognize the disk correctly. You will no longer receive such an unreadable disk error. If you still need help, watch this video to fix "the disk you attached was not readable by this computer" on Mac.
If the "the disk you inserted was not readable by this computer" error still exists after trying all the methods, we recommend you back up the drive. Purchase a new device and be prepared for a drive failure soon.
Repairing the unreadable disk is time-consuming. Thus, you should take measures to protect your disk. Here are some solutions to avoid an unreadable disk on a Mac.
We listed four solutions to help you fix the "the disk you inserted was not readable by this computer" error on Mac. If you have the same issue on your drive, follow the tips on this page for help. Some of you may lose some useful files during the process, don't worry.
EaseUS Data Recovery Wizard for Mac can scan and locate all your files with just a few clicks. It's your turn to make your drive work normally again.
Read the questions and answers below to get additional help.
1. How do I fix the disk you attached was not readable by this computer on Mac?
To fix the disk you attached was not readable by this computer, follow the solutions below:
2. How do I fix an unreadable SD card on my Mac?
Don't worry if your SD card not reading on Mac, and you can fix the error with effective solutions:
3. Why is my SD card suddenly unreadable?
If your SD card becomes unreadable, its file system is probably damaged, and you need to format it before you can use it again.
4. Can I recover files from an unreadable SD card?
Yes, you can recover an unreadable SD card with the steps below:
5. How to fix an unreadable USB flash drive on Mac?
To fix an unreadable USB drive on a Mac, first, open Disk Utility from Applications > Utilities, select the drive in the sidebar, and click First Aid to repair file system errors.
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