How to delete partition on usb thumb drive

• From Command prompt type diskpart

• Within Diskpart, use the List Disk command to check which disk the USB device is. The USB device should be obvious; in my case, it's the 14GB disk.

DISKPART> list disk

Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 465 GB 1024 KB
Disk 1 Online 14 GB 0 B

• Once the disk is known, select the disk and run the rest of the displayed commands (change "disk 1" to the number of your disk):

DISKPART> select disk1

Disk 1 is now the selected disk.

• Clean the partition

DISKPART> clean

DiskPart succeeded in cleaning the disk.