How to change hard drive from Read permission to Write on Mac

Want to know how to change a hard drive from read-only on a Mac? If you’ve plugged in an external disk and Finder refuses to let you add or edit files, this is the only article you need to read.

Diagnosis: Why is my drive "Read Only"?

So, before you learn how to change a hard drive from a read-only Mac, you need to understand what's happening.

1. Check with Get Info

1. In Finder, select your external drive.

2. Right-click and press Get Info.
   

   Format under General. If it says NTFS, that is a Windows format macOS can read but not write.

   Sharing & Permissions at the bottom. If your user shows Read Only, that’s a permissions issue.

3. If it’s an SD card or thumb drive, check the physical lock switch on the card or adapter. If it’s slid to Lock, the Mac will mount it read-only.

2. Quick health check

1. Open Disk Utility from Applications > Utilities.

2. Select the disk and the volume.

3. If the volume is mounted Read-Only after an error, you’ll need First Aid before any permission change will stick.

Permissions: How to change a hard drive from read-only on a Mac

This only applies if the disk is a Mac-writable format like APFS or exFAT.

1. In Finder, select the drive, right-click, and press Get Info.

2. Click the lock at the bottom right, enter your admin password or Touch ID.

3. Next, under the Sharing & Permissions section, set Privilege for your user to Read & Write and confirm if requested.

4. On some external drives, you’ll also see Ignore ownership on this volume. Turn it on to avoid owner conflicts between Macs.

If the Privilege dropdown is grayed out, the disk is either not a writable format on macOS or the volume has errors.

Handling NTFS Drives

By default, macOS can read NTFS but not write. You have two choices:

1. Reformat to a Mac-writable format (erases the drive)

1. Back up all your files first. Do not skip this step.

2. Open Disk Utility and select the volume (or the disk if you want a full wipe).

3. Click Erase and choose exFAT or APFS.
   exFAT if you share with Windows and Mac.
   APFS if the drive stays on Mac only.

4. Click Erase and copy data back.

2. Use a third-party NTFS driver

Tools like Paragon or Tuxera add reliable NTFS write support on macOS. Install, restart, and you can write to NTFS without reformatting.

Before you copy a whole backup back and forth, trim obvious bloat and junk. I use Space Lens from CleanMyMac. It can scan your external drive for hidden digital junk and system shadows, making sure your backup is clean before you wipe the drive; here’s how:

1. Open CleanMyMac — get your free trial here (seven days free).

2. Click Space Lens > Select your drive > Scan.

3. View, sort, and remove what you no longer need.

Repairing disk permissions and errors

When you’re trying to change a hard drive from read-only on a Mac, if First Aid finds any errors, you’ll need to fix those first; here’s how:

1. From Finder > Applications > Utilities > Open Disk Utility.

2. Select a volume, and click First Aid. If it doesn’t bring back issues, then repeat this at the container level.

3. Eject and reconnect the drive, and try your permissions again.

If a particular folder stays locked:

1. Select the folder > Get Info > Click the unlock icon (bottom).

2. Set Read & Write > gear menu > Apply to enclosed items…

If that fails, try to create a new folder on the same drive and move your files there. Restart your Mac, then delete the old file.

Light maintenance always helps after you repair a drive. I run CleanMyMac > Smart Care to clear caches and rebuild a few system indexes, so Finder stops tripping over stale metadata while I test the drive again.

Using Terminal for a one-time fix

This really should be a last resort. If you only need a one-time copy off an NTFS disk and accept the risk, you can attempt an fstab mount, but without a third-party NTFS write driver, this will still mount read-only. There are quite a few steps here, but I’ve tried to break them down and keep it as simple as possible.

1. With your NTFS drive connected, open Terminal. Run the below command to find its identifier (for example: disk3s1):
   diskutil list

2. Next, run the below to locate its Volume UUID:
   diskutil info disk3s1 | grep 'Volume UUID' (replace disk3s1 with your actual identifier)

3. Create or edit fstab:
   sudo nano /etc/fstab

4. Add this line, replacing with your UUID:
   UUID=YOUR-VOLUME-UUID none ntfs rw,auto,nobrowse

5. Save with Control - O, press Return, and exit Terminal.

6. Disconnect your drive properly, then reconnect it.

7. Go to Finder > Go > Go to Folder and enter the following:
   /Volumes

8. Open the drive from here and copy the files you need. When you’re done, remove the fstab line to avoid surprises: sudo nano /etc/fstab (delete the line, save, exit)

Avoid read-only headaches

Always start with the right format and avoid read-only headaches later.

• APFS: Best for Mac-only drives and SSDs. Required for modern Time Machine targets on macOS.

• exFT: For drives you share with Windows and game consoles.

• MS-DOS (FAT32): Only for legacy devices.

That’s it, that's everything on how to change a hard drive from read-only on a Mac.