I formatted my flash drive using HP USB Disk Storage Format Tool with MS-DOS 6.22 system files but I could not boot up from it. I made the necessary changes in my BIOS in order to boot from an USB device but after restart I got a non-system disk error. I have tested the image file with floppy disk and it worked fine. How do I know my USB flash drive supports booting from it in general. I do not know its vendor. Actually it is a noname (general disk) stuff, I have won it as a prize with some stupid game. I took a look at the drive in Disk management section and it was displayed as an active, primary partition. Any idea?