Vista Printer Problems

I am trying to wirelessly connect a HP laptop running Windows Vista Home Premium to a Xerox Phaser 6200B connected to a desktop PC running Windows XP Media Center Edition (SP2). I can see the Xerox printer in the list of shared network printers but when I try to make the connection from the laptop I receive an error saying, “Access Denied”. I have all security permissions imaginable enabled for printing and management; with all the settings I have set, I don’t see a reason for the error. Is there something I’m missing?