Vista - how to rename a printer port on a network

My printer stopped working from my notebook which is on a home network and is
connected to my PC. I cannot seem to install the computer using a new port.
I see the old port name (which includes my old PC name), but when I try to
connect up using \\Carl-PC\Printer4 it tells me the path is not found.

If I choose to use an existing port, I can see the old named port. However,
i think I need to rename it or delete it as I get printer errors when
printing from the notebook, but not from the PC itself. The PC uses XP and
the note book uses Vista.

I use a TrendNet router and the printer is a HP 6L. I use Network magic to
monitor my network.