Summary: You will find 3 methods to solve Mac external hard drive read only error quickly. Free download iBoysoft NTFS for Mac if external hard drive is read only on Mac because it is formatted with Microsoft NTFS file system.
After an external hard drive with Mac compatible file system is connected to a Mac computer, you can open it and have full read and write access. It is not impossible that external hard drive is read only on Mac, preventing you from copying or transferring any files from Mac to the external hard drive.
For example, many people have reported that their WD My Passport read-only on Mac and don't know how to fix Seagate external hard drive read only on Mac.
This article discusses 3 quick solutions to help you solve Mac external hard drive read only error, based on the 3 main causes listed below:
- External hard drive is NTFS formatted
- Disk permission is changed as read only
- External hard drive is corrupted
Case 1: The file system on external hard drive is NTFS
Most external hard drives and SSDs are previously formatted with Microsoft NTFS for Windows use. NTFS file system is not a Mac compatible file system because macOS only reads it but not allows writing to it.
If you try to copy or transfer files from Mac to an NTFS-formatted external hard drive on Mac, you'll see the greyed-out forbidden symbol shown as below. After opening the disk, all documents show read only or locked.
What file system does Mac use then? Mac can fully support APFS (macOS 10.13 or above), HFS+, and FAT family. If you find your Apple external hard drive read only, the first thing to check what file system the external HDD or SSD is formatted, NTFS or not.
How do I know if my external hard drive is NTFS file system?
Simply, you can check file system information by viewing its disk information either in Disk Utility or in the Finder.
Method 1: Check file system info in Disk Utility
- 1. Click on Launchpad at the dock of your Mac and choose Other in the menu.
- 2. Choose Disk Utility among these utilities and open it.
- 3. When it is launched, click on the external hard drive you have read-only problem with in the left sidebar. You will see an obvious "Windows NT File System" in the right column.
Method 2: Check file system info in the Finder
You can also check this in the Finder with a few clicks.
- 1. Open the Finder and right-click on this external hard drive.
- 2. Choose Get info in the context menu.
- 3. You will see "Windows NT File System (NTFS)" after File system if the read-only drive is formatted with Microsoft NTFS file system.
How to fix NTFS external hard drive read only on Mac:
After confirming that it is the Windows NTFS file system that makes your external hard drive read only on Mac, you can go head to fix this problem by either reformating the external hard drive on Mac or using an NTFS for Mac app.
Solution 1: Using NTFS for Mac tool
If you have important files on this external hard drive, and you frequently swap your work between Windows and Mac, reformatting definitely is the last solution you would resort to. Reformatting the disk will delete all files.
If you want to fix external hard drive read only on Mac without formatting, using a cross-platform NTFS driver for Mac is the best choice.
iBoysoft NTFS for Mac is the best pick. This easy-to-operate NTFS for Mac software can make the NTFS read only external hard drive writable on Mac.
About iBoysoft NTFS for Mac
iBoysoft NTFS for Mac can mount NTFS external hard drives in read-write mode on your Mac, granting people full access to read NTFS drive on Mac and write files on NTFS-formatted drives.
iBoysoft NTFS for Mac- Best NTFS Disk Management for Mac
- Grant full access to Windows NTFS file system on Mac
- Read, write, modify, transfer, and delete files on NTFS drives on Mac
- Repair NTFS disks on Mac
- Erase disks to NTFS file system on Mac
- Support macOS 12 to macOS 10.13
- Fully support Apple M1, M1 Pro, and M1 Max Mac
How to access external hard drive on Mac with iBoysoft NTFS for Mac:
- 1. Free download and install iBoysoft NTFS for Mac on your computer.
- 2. Connect NTFS external hard drive to Mac and launch iBoysoft NTFS for Mac.
- 3. Write to NTFS external hard drive after the external hard drive is mounted in read-write mode successfully.
Note: If you can't write to your NTFS drive after installing the software, you need to install an NTFS driver by iBoysoft and enable System Extensions as the pop-up indicates. Then, the NTFS disk will be mounted in read-write mode.
Solution 2: Enable NTFS read-write with Terminal (not recommend)
You can also try the experimental method to enable NTFS read-write support with command prompt on your Mac. In this way, you still do not need to reformat external hard drive on Mac. All attemps are at your own risk.
Warning: Do not use this method as a long-term solution to solve NTFS read only external hard drive on Mac, especially on drives that contain important files. Meanwhile, be careful with the command line, in case that you input a wrong command and cause unexpected damages to your Mac and drives.
How to change external hard drive from read only on Mac with Terminal:
- 1. Click Go at the upper right of your desktop and go to the Applications > Utilities > Terminal.
- 2. Input "sudo nano /etc/fstab" to edit the fstab file (supply your password when prompted).
- 3. Type "LABEL=NAME none ntfs rw,auto,nobrowse" in the editor window for the fstab file. (Be sure to change the word NAME to the name of your drive)
- 4. Press Control + O to save the file, followed byControl + X to exit.
- 5. Unmount your NTFS drive and attach it again.
Solution 3: Erase external hard drive to exFAT/FAT32
If your NTFS external hard drive is new and empty, giving it a Mac compatible file system is a good idea.
How to reformat external hard drive on Mac? You can just go to Disk Utility and Erase it. There are several formats you can choose, and erasing this disk into which file system depends on how you intend to use the drive.
- APFS: If you plan to use the drive on macOS 12 Monterey, 11 Big Sur, 10.15 Catalina, macOS 10.14 Mojave, and macOS 10.13 High Sierra, you can format it into APFS for better read-write speed.
- HFS+: Also known as Mac OS Extended, use this Mac file system if you are going to open this external hard drive on macOS Sierra and earlier Mac operating systems.
- FAT32/exFAT: Best option if you need to view files and transfer files to external storage devices both on Window and Mac.
How to Format an External Hard Drive on Mac?
Read this detailed guide to format your external hard drive on Mac. You can format external hard drive for PC and/or Mac.Read more >>
Case 2: Disk permission is read only
User can set up file permissions to determine who can delete or modify a file or program copied to a certain drive. Thus, if the external hard disk has read only permission, there is no suprise to see a message informing you that Mac external hard drive is read only when saving changes.
You can right-click on the icon of your disk and choose "Get info", scroll down to check the disk privilege you have. If it shows read only, you don't have the permission to write to the external hard drive on this Mac.
You can either use another Mac or use this external disk on Windows to bypass the issue. No second computer available? Try to change permissions on the external hard drive on Mac.
Solution 1: Change permission on external hard drive on Mac with admin privilege
To solve Mac external hard drive read only error due to limited permission, you can easily alter it if you are an administrator.
How to change read only permission on Apple external hard drive to read & write?
- 1. Open the Finder and find your external hard drive in the left sidebar.
- 2. Right-click on this drive or volume and choose Get info, and then scroll down to Sharing & Permissions.
- 3. Extend this column by clicking on the triangle symbol, and then click on the Lock icon.
- 4. Input your admin username and password, and click on Read only, then change your privilege as Read & Write in the right column.
- 5. Click the gear button (Action menu) at the bottom of the window, choose Apply to enclosed items, and then click OK to confirm the action.
- 6. Click the Lock icon to save changes.
Solution 2: Ignore Permissions on external hard drive in the Finder
Mac operating system includes a setting to allow an administrator to ignore permissions on external drives, so all files should be fully accessible regardless of their permissions settings. Here below are steps to ignore the permissions on external hard drives without formatting:
- Step 1: Select the external hard drive in the Finder sidebar, and then press Command + I to get information of the drive.
- Step 2: Click on the Lock icon with admin password and then click on the arrow by the Sharing & Permissions tab near the bottom of the window.
- Step 3: Check the box to Ignore ownership on this volume.
- Step 4: Click the Lock icon to save changes.
Case 3: External hard drive is corrupted
Can't change permisions on Mac? To avoid further corruption, internal disk logic errors will prevent the system from writing to or changing file permissions on an external hard drive. Or even worse, this external disk will not be mounted for use at the beginning.
Solution: Repair external hard drive with First Aid
Fortunately, Mac has a built-in and free disk repairing tool in Disk Utility named First Aid that can help you check and fix minor file system errors. Follow the guide below to fix read-only external hard drive without formatting in Mac's Disk Utility app.
- Step 1: Open Disk Utility from Launchpad and Other folder.
- Step 2: Select the disk from the sidebar that is read only.
- Step 3: Click First Aid at the top and choose Run.
- Step 4: Wait for a short time and see what feeback you get from running First Aid. If it returns with "First Aid process is complete" message, click Done to close the window.
Then you try to remove the external hard disk and connect it back to the computer to see if you can open it and copy files from Mac to it.
If First Aid doesn't make any differences, you need to reformat the external hard drive on Mac. You should rescue files off the external drive with data recovery software.
iBoysoft Mac Data Recovery, the free data recovery software, works to recover data from corrupted, unmounted, inaccessible hard drives with only a few clicks: Scan, Preview, and Recover. It is compatible with macOS Monterey, Big Sur, Catalina, Mojave, and earlier OS versions.
[Solved] Disk Utility's First Aid Repairing Process has Failed on External Hard Drives
This article tells you what to do when First Aid failed in repairing external hard drives. Read more >>
Generally speaking, Mac external hard drive read-only issue appears when it is formatted with NTFS file system, corrupted, or set with read-only disk permission. The solutions above are useful to fix external hard drive read-only on Mac without formatting.
To solve Mac external hard drive read only error due to Microsoft NTFS format, free download iBoysoft NTFS for Mac is the most efficient way.