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How to fix the external hard drive read-only on Mac?

After updating to El Capitan yesterday, my toshiba external hard drive is now only giving me permission to "read only". How do I fix this?

Best Answered by

iBoysoft author Eudora Liu

Eudora Liu

Answered on Tuesday, January 27, 2026

When your external hard drive shows read-only, you can only view the drive but write, copy, and delete on it. There are a few reasons that may cause your external hard drive read only.

  • The file system is NTFS.
  • The Permission Settings is not ignored.
  • The hard drive has formatting errors.

Before you fix your external hard drive read-only, you can check whether it has been formatted with NTFS. If it does, you can use iBoysoft NTFS for Mac to mount your disk, which is a powerful tool for you to mount your Windows NTFS volume in read-write mode. Using this software, you can delete, edit, rename, and write files on NTFS drives in macOS & Mac OS X freely without formatting.

  1. Free download and install iBoysoft NTFS for Mac.
  2. Connect your NTFS drive to your Mac.

After you connect your drive successfully, you can mount your NTFS drive in read-write mode.

If your external hard drive has not been formatted with NTFS, you can follow the below solutions to fix your external hard drive read-only on Mac.

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