unable to send plot directly to plotter

Hi,

 I'm trying to send my V8 plots directly to an HP 500 DesignJet plotter from a standalone laptop computer using the HPGL2 driver.  This has previously worked fine when I had a cable connecting the parallel port on a standalone desktop computer to the plotter.  Now, I'm using a laptop without a parallel port and must use a USB cable to connect to the plotter.

 

 Here's how I have the HPGL2.PLT file edited:

 default_outFile/auto_overwrite= "USB001"

(removed semicolon at beginning of line)

 

Previously, this worked great when I had "lpt1" at the end of the line and sent the plot via a parallel port on another computer.

I do see a comment at the bottom on the screen in MicroStation that states "finished creating print USB001".

How can I get the plots to be sent out directly to the plotter rather than creating plot files to be sent out later?  Thanks very much for any help with this.

 

Rob