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Jeffrey0827 Author

Level 1

9 points

Formatting a USB Drive to GUID

When I try to erase and format a USB drive from the MBR to GUID I can not find a way to do that. The partition button is grayed out and I feel stuck.

iMac 27" 5K, macOS 10.14

Posted on Apr 1, 2019 1:55 PM

Top-ranking reply

macjack

Level 10

111,448 points

Posted on Apr 1, 2019 2:00 PM

To format a drive using Disk Utility first be sure you see the entire drive. In Disk Utility menu bar the last icon on the left "View" set to "All Devices". Then choose your entire drive (Uppermost, unindented icon). Format Mac OS (Extended) GUID Partition Disk. Erase.

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Formatting a USB Drive to GUID

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