But the 'Scheme' popup menu does not appear in the panel. If I select the secondary item in that list (Lexar), I can successfully do a format operation. No matter what Scheme I choose, I get an error when trying to format the item higher in the hierarchy in the sidebar to the left (Lexar USB Flash…), as shown in the screen shot above.
Mysterious error when formatting higher item The third one ( Apple Partition Map) is for booting old Macs (68K and PowerPC rather than Intel chips). Why is this offered as a scheme for 'Mac OS Extended (Journaled)'? That really threw me, and prompted this Question. (Optional) If available, click Security Options, use the slider to choose how many times to write over the erased. Click the Format pop-up menu, then choose a file system format. Click the Scheme pop-up menu, then choose GUID Partition Map. The second one ( Master Boot Record) is old, from the 80's DOS 2, for old PCs. In the sidebar, select the storage device you want to erase, then click the Erase button. Booting is not an issue for my use of this flash drive.
I know the first one ( GUID Partition Map) is for booting modern Macs. When using Disk Utility 16.3 with macOS Sierra to format a 'thumbdrive' USB 3 Lexar flash drive (64 gigs), when I choose a Format of ‘Mac OS Extended (Journaled)’, I get a list of three Scheme items:
