mount usb for kiosk desktop

[oxy]

I'm very new user of knoppix, and was wondering of the cheat code at boot time
boot: knoppix desktop=kiosk url=file:///mnt/sda/123.html
but when I enter the kiosk, it tells me that it could't find the file(while it really does exits),
and I thout that, it might be the problem of it didn't mount the usb drive in this situation,
is there anyone knows how to mount the flash drive for the kiosk desktop, or knows what my problem is, or knows an other way to achive this goal?
I wish I could set the url of the kiosk to my file in the flash usb instead to the internet
thanks a lot

[SiKing]

If you boot Knoppix "normally" - no cheat codes - does it boot without any problems? Can you read your USB drive?