Hi! Need Cure 4 Unrecognized HP PSC500 All in 1

Sorry this is long and maybe should be in Hardware or XP forums but my OS software & it's settings seem fine....

I really need help on this one. I've spent more than 20 hours on this alone!

I have a older HP PSC 500 all-in-one printer/photocopier/scanner from back when these were many hundred $ units.

It has always worked well including when my last computer died (printed the day before). It photocopy & print works fine in stand alone mode (not directed by computer).

I'm trying to get it working on my newer HP
MT5100 desktop w/ Win XP Pro SP1. The last computer was also Pro SP1 and the printer is age consistent w/ the OS & indeed, the native XP print drivers were written by HP.

I have followed all directions contained in "How to install..." page for this model of printer located at HP:
http://h10025.www1.hp.com/ewfrf/wc/document?docname=buu01853&tmp_task=setupCategory&lc=en&dlc=en&cc=ca&lang=en&product=58710

Also have run XP trouble shooter but can't help in the end.

But "print" always fails with the red X onto the icon on task bar. Will not print in any mode a simple .txt nor even the built in "test page".

WEIRD BIT: The PSC is listed as recognized model in the list of compatible & drivers are there & native.

In CP> Printers, it shows as "Ready"/with check mark as default/only printer.

In Device Mgr it shows as installed on LPT 1, ECP, working properly, correct ranges assigned & all settings seem correct according to the set up instructions. Set as direct to printer (not online/ networked).DMA 3 Single IRQ 7 "no conflict".

Driver Mgr. shows all correct (no roll back possible). In fact the set up instr. specifically state:
"USE XP DRIVERS NOT HP INSTALL SOFTWARE & DRIVERS! Install the drivers built into Windows XP
Follow these steps to install the print drivers built into Windows XP...."

WEIRDNESS# 1: When I double click "My Computer", I show HD C:, Removable DVD D:

But on last machine was & I believe there should be another line below with:
"Printers & Scanners (cameras) listing the HP PSC500 BUT there isn't any such!

Weirdness# 2: Plug & play doesn't pop up because it's already installed.
Tried un-installing complete & manually re-inst. but no change at all.

Weirdness# 3: There's a comment in install
that the BIOS must be set for the LPT1 port as "ECP" first EPP + ECP second on down the list. It also states:
"Even if the parallel port entry is "ECP Printer Port" and has two input output ranges, the mode may be "ECP and EPP." ?ECP and EPP? mode may not work correctly.".

In attempting to change in BIOS, I get only HP set up facility (not expected true BIOS entry option & no name of bios maker only alpha numeric listing)which does show the the periph. & indicates as
"EPP + ECP" only. No other sub list of options & no apparent way to alter to ECP first or only!

The connecting cable from the printer for the parallel port is hardwired at printer end. Standard (large 2 times monitor connector size) connector at computer end.

Could this new MB, have an altered/updated to save money size change to lesser protrusion?

I ask because although the thumb screws are aligned correctly & they're tightened down hard to the stops on the machine mounted
male, to my eye, the female corded connector barely reaches to cover the male.
Looks like it should be capable of going down another 1/8th of an inch or so but is prevented by manufactured nut which is part of the finger screw itself on the inner (computer side) of the connector.
My EYE is not trained but still...?!

It was standard so should be ok but if full connection NOT made could explain story but worked fine on last machine both w/ Intel MBs (old: 865 GBF new: 915).

I don't want to throw away a VERY well made
& working Rolls-Royce of an all in one
only to replace with a USB piece of disposable CR*P!! HELP ME , PLEASE!! TIA. Sandy