This is an old post I just saw, about the "Create MS-DOS boot disk" option in floppy disk formatting. (Applicable to XP and later versions,)
This function creates a WinME DOS boot disk. Since we don't have a floppy drive installed now, we can't see it, but this function still exists in Win7. You can see it after installing a floppy drive. If you don’t believe it, you can search the help of Win7: “Format DOS” and select “Format Floppy Disk” in the search results.
The files in the formatted floppy disk cannot be found in the system. It is actually hidden in system32diskcopy.dll. Open it with Exescope, save the resource binfile1, and get a floppy disk image. Open the saved file with UltraISO and you can see the contents of the floppy disk.
Supplementary content (2011-9-19 17:01):
This floppy disk does not have extra drivers, and it does not even support optical drive drivers. It is very suitable for upgrading BIOS under DOS.
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