Could be several things causing this. You said it is a network printer, but then said primary computer is XP. Is it hooked to the XP machine? From my experience, printers on XP machines occasionally lose their drivers. Go to the XP machine and make sure the printer is in the printer folder, and active. Do a test print to be sure. Then make sure it is still shared (things like this can change with updates). If all this is OK, go to the Vista machine and remove the printer. Then go to add printers, and add a network printer. Sometimes, if it is a network printer, it will show up in "my network" - if so, right click and add printer. If you add the printer usually the computer will use the currently installed drivers. If it is a shared printer, go to network, double click the XP machine, and the shared printer should be there. right click and add. Once you have it working, go to printers and delete or remove the faded-out printers that don't work and be sure to set the newly installed printer as your default.
on Jun 18, 2018