You can do this by using
diskpart
on Windows:- Open an elevated command prompt.
- Run
diskpart
list disk
- Note the disk number that corresponds to your USB drive (it should be obvious going by size)
select disk X
where X is the number from step 4list partition
- There should be two, numbered 0 and 1, each about 7 GBselect partition 0
delete partition
select partition 1
delete partition
create partition primary
exit
- Exit Command Prompt (type
exit
or just close the window) - In Windows, go to Computer and try to open the disk. It will ask you to format it.
- Format it with the default settings and give it a name if you want.