External won't work on Mac after using on PC

Mar 27, 2015
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My Toshiba External USB drive stopped working on my Mac air after I downloaded some files on a PC. It worked numerous times on the PC and then I brought it back home to use on Mac. Now, it won't show up on finder but can be found on Disk utility. I cannot manually mount it there. Repair disk and verify seem to finish but still won't mount. It was originally formatted as Mac OS Extended (Journaled). Now it appears to have been changed to Windows NT Filesystem (Tuxera NTFS). The PC did not prompt me to re-format or do anything to the Hard drive.

How can I get it to work on Mac again?

Thank you.


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Staff member
Nov 15, 2009
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North Louisiana, USA
Your Mac's Specs
M1 MacMini 16 GB - Ventura, iPhone 14 Pro Max, 2015 iMac 16 GB Monterey
Unless you added a third party driver to the PC using that driver with a PC means that something changed the drive formatting from HFS+ Extended Journaled (Mac) to NTFS (PC). Windows-based systems cannot read Mac formatted drives without third party drivers.

Some of the other guys may have a better idea but I suspect that the Tuxera NTFS driver might be contributing to the problem. A quick google found numerous reports of similar problems including many on the Tuxera forum. No solutions though.

Even though it's not free I much prefer the Paragon NTFS driver for Mac. It seems to be much more reliable.

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