In previous versions of MacOS, I recall that Disk Utility provided an option to select the partition scheme (GUID, MBR, or Apple).

If I formatted the USB key without changing the scheme to MBR, I could not read it on a Windows machine.

But now there is no option in High Sierra.

How do I format the USB key with FAT and MBR?


1 Answer 1


I thought I had the same issue but it's probably because in the view options at the top left corner of the Disk Utility window, "Show Only Volumes" is selected.

In order to change the partition map, it seems you have to select the actual disk. So simply select view - show all devices, then select the actual drive you're trying to reformat, then when trying to erase, you should have the option to choose a partition scheme.

Hope this helps!

annotated screenshot

  • 3
    Oh my! Thanks John. It seems so easy now, i've been wracking my brain trying to solve this, it was so simple I feel stupid. I'm sharing this in other forums where people are having the same issue. I hope that's ok. Thanks so much.
    – Joey87
    Jan 5, 2018 at 0:43
  • 27
    What ever happened to the Mac? It used to be simple, now it's loaded with mystery meat and unixy conventions. Apple has lost the script.
    – ATL_DEV
    Feb 2, 2018 at 16:49
  • 6
    I wasted 2 hours of my life trying to figure out why my TV could read a new USB stick, but not this one, all because this view was hidden by default. Apple logic: "Let's hide the advanced options in this advanced feature" Dec 26, 2018 at 4:12
  • 1
    @AndrewDunning I tried today and it worked fine. Aug 7, 2019 at 8:06
  • 1
    Solution works in 10.15.7 Catalina
    – gatorback
    Nov 20, 2020 at 1:17

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