Printing problems with LT2000 on WinXP Pro

Hello all,
We got a new pc with WinXP Pro on it and have had problems printing eversince. Before we had Win98SE.
We plot on a HP Laserjet 5N.
When we first started using LT a couple of years back on the 98se machine we never had any issues with plotting, so we never thought about using plotstyles.
In the plot command this is left to "plot style table = None".
Now on the WinXP Pro machine with the same LT version and the same HP 5N this result in prints in all shades of grey.
As if the printer is trying to print colors.
This i.m.o. means that WinXP Pro has another way of adressing the HP 5N since nothing else has changed.
How to solve this? Using a plot style would help, but that would mean changing ALL previous drawings because of XP.
Is there no other way? Does anyone know of a way to change the way the HP 5N is adressed by WinXP Pro?

So we are looking for a way to make WinXP Pro print like Win98se did, we are not looking for a plot style.

Many thx for any help at all.
Kind regards,
Patrick