Parallel Port Based Printer Malfunction

>I have a shuttle xpc barebone system which has no external parallel port.
>It
> seems to have an onboard one but this is not connected and has no external
> interface.
> I also have an old HP LaserJet 6MP - very reliable and solid printer that
> has worked for years. Since upgrading the PC I have been unable to use it
> and
> need now to solve the problem.
>
> Initially I purchased and installed a PCI card with a parallel and two
> serial ports on it. Its a NETMOS card and the drivers all seem fine. I
> have
> one on another PC (in another country) and it works fine for the serial
> ports
> (another Shuttle barebone without a serial interface) However, the printer
> does not seem to respond at all when connected to the parallel port. The
> lights flash a bit the first time I try to print but then nothing.
>
> I then tried out a USB to parallel port cable. On XP it said there was no
> need for drivers and came only with ones for Win98. It said it installed
> ok
> but I couldn't see what device had been installed when checking the
> devices
> manager. There are two IEE 1284.1 devices but they both seem to relate to
> the
> USB based HP750 that does work fine. I have tried to use the LPT ports
> (all
> of them) plus the USB virtual port for the printer but none seem to work.
> I
> can't really see a way to isolate the problem.
> The printer has been moved from HK to the UK but worked fine in HK and was
> shipped in its original packaging and does all the self tests fine so I
> doubt
> there is a problem there.
>
> I just can't quite see what to try next to get this going. I really need
> it
> now and its driving me nuts. Any clues would be much appreciated?
>
> Many thanks
>
>