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USB drive is read-only on Mac, how to fix it?

I wish to allow my Mac and Windows computers to share a USB disk. I can't write to FAT32 or ExFAT USB devices, despite everything I've read saying that my Mac should be able to read and write to them. I've attempted the recommended fixes: On my Mac, adjust the permissions and reformat the HDD. To inspect and fix the drive, use DiskUtility First Aid; however, none of them are working. The drive is readable, but I am unable to write to it. I've tried a few different USB drives, but the issue continues. This is a FAT16 disk. There is no way to change the "You can only read" permissions.

Best Answered by

Amanda Wong

Answered on Tuesday, August 27, 2024

If you have already checked the file format and it is macOS-compatible, reformatted the drive, and repaired the USB disk with First Aid, but you can't change the read-only permissions on the USB flash drive, then your Mac may be managed by an organization and is not allowed to write to external drives.

As you said, you have admin access, but you tried some fixes and you still can't write to the USB flash drive, then your device is probably managed by an organization, you should check the organization's policy to see whether you are allowed to write access external drives.