Is there an option in the BIOS to turn on USB legacy mode or enter the TAB key during the bootup and add "nousb2" on the startup strings at the end then hit enter.
Also try re-imaging your USB Drive, and dont forget to make it bootable.
And if your booting from a USB flash drive, there is no install(if you want to continue to use it as the boot media).... just boot right to the OS.