Had a similar problem "way back when" with an HP scanner/printer combo. The manual said (if memory serves) to connect the scanner to the LPT port and the printer to the scanner, but the PC wouldn't "see" the printer.
In the end I just swapped them round, so the printer was on the port and the scanner was on the printer - et voila! Worked for me, hope it helps.
Good luck.
[I forgot, drivers, drivers, drivers!Have a look at the manufacturer websites and be sure you have the latest offerings.]
[This message has been edited by Squiddley (edited 22 June 2001).]