You cannot print directly to USB printer from DOS application. See Re: USB printing Message #800914 for workaround.

>This is the story. Printer connected to USB port. On a properies window it says 'USB001 port'.
>I tries a few things, but was not able to print even from DOS:
>1. DIR>USB001
>2. COPY filename USB001
>3. PRINT file
>4. MODE USB001 LPT1
>
>By the way, printer does not have (!?) a parallel port, thanks to Dell.