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With the introduction of the Apple Silicon M3 chip, the Mac computing landscape has shifted dramatically, with improved performance, efficiency, and a more streamlined user experience in the offing. However, as with every technological evolution, it has ushered in its fair share of compatibility issues.

One of the most common problems with the Apple Silicon M3 Mac is that external hard drives are read-only, meaning that users cannot write to or otherwise alter the drive's contents. This annoying issue can slow down your work and make it difficult to handle your files, but there are several ways to fix it.

Why Does M3-chip Mac Only Read My External Hard Drive?

There are many possible causes for an external hard disk to be Mac-only. The three most frequent are listed below.

Formatting Problems:

Errors in the formatting of any hard disk can cause various issues. Your external hard drive will be rendered read-only as a result. Errors in the drive's formatting will prohibit you from saving any data, so you may have seen a notification that the external device was mounted in read-only mode.

Permission Settings:

Like your local hard drive, an external hard drive is subject to the permission settings of your operating system. All the files and folders on the device are now subject to these permissions.

If Mac is running a different operating system won't be able to read the drive or make the necessary permissions changes. In other words, you don't have authorization to write to the external HDD on a Mac and won't be able to use your disk as usual.

The External Hard Drive Has the NTFS Format:

The file system format of your drive is important because macOS doesn't support all of them. More specifically, macOS doesn't support NTFS. The most typical issue caused by this incompatibility is permanently setting your hard disk to read-only.

NTFS external drives are unique to Windows devices; thus, macOS can't write to them. Right-click your device and left-click Get Info to check NTFS.

fix external hard drive read-only on M3 Mac

How to Fix Apple Silicon M3 Mac Read-Only External Hard Drive Issue?

1. Change File System Format:

Launch "Disk Utility" on your M3 Mac and double-check the external hard drive's file system format. You can convert the drive's file system from NTFS or exFAT to Apple File System (APFS) or Mac OS Extended, both supported by macOS.

  • Launch "Disk Utility" by navigating to "Applications" > "Utilities" > "Disk Utility".
  • Choose the portable hard drive from the menu on the left.
  • Select "Erase" and then a file system compatible with your device (such as APFS or Mac OS Extended) to continue.
  • To reformat the drive, stick to the on-screen prompts.

fix external hard drive read-only on M3 Mac

Please back up your data stored on the external hard drive before you erase the external hard drive. If not, you can use a data recovery app to get lost files back.

Recover Lost Data from An Erased Hard Drive

Recover Lost Data from An Erased Hard Drive

Data recovery software takes only three steps to completely recover lost data from a hard drive which is erased by Disk Utility.

2. Adjust Permissions and Ownership:

Make sure the external drive has read/write access and adjust the appropriate permissions:

  • In Finder, choose the disk.
  • Select "Get Info" from the context menu, or use the shortcut Command + I.
  • The "Sharing & Permissions" tab is where you need to be.
  • Click the lock symbol and enter the administrator password to unlock.
  • Change your account's settings to "Read & Write".

fix external hard drive read-only on M3 Mac

3. Use Third-Party Drivers/Software

If the external hard drive is an NTFS drive, you don’t need to format it. Just install a NTFS for Mac tool on your M3-chip Mac, then open this tool on your Mac.

Make sure the external hard drive is connected to your M3-chip Mac, and then select the external hard drive, click on Enable Writable button. (If the external hard drive is unmounted, click on Mount button.)

use NTFS hard drive on M3 chip Mac

4. Verify Cable and Connection:

If using an external hard drive with your M3 Mac, check that the USB cable is plugged into both devices. Test using a different USB port or cable to rule out connection issues.

5. Repair Disk Errors:

If there are any faults or corruptions on the external hard drive, use the "First Aid" option of Disk Utility to fix them.

  • Open "Disk Utility".
  • From the drop-down menu, choose the faulty drive.
  • After selecting "First Aid", select "Run" to begin disk repair.

fix external hard drive read-only on M3 Mac


Troubleshooting an Apple Silicon M3 Mac's read-only external hard drive can be difficult, but these techniques often work. Implementing the proper remedy requires understanding the root problems, such as file system incompatibility, permissions, connection issues, or drive errors.

Before reformatting or repairing backup important data, some workarounds need third-party software or extra procedures. However, fixing the read-only bug can restore full functionality and enable data management across external drives and Apple Silicon M3 Macs.

These detailed troubleshooting procedures can fix the read-only issue and maximize external storage devices on Apple Silicon M3 chip-based Macs.

DoYourData Author

Written & Updated by Justin Kenny

Justin Kenny is a writer & editor of DoYourData. He joined DoYourData in 2016 and focuses on writing articles about Windows data recovery, Mac data recovery, external device data recovery, hard drive clone, data erasure, Mac cleanup, computer issue fixes, etc. He is a super fan of Apple devices and is big on testing new digital device and system utility software.

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