Update: A Solution

1. In Vista PC’s go to “Control Panel” - “Printers” - “Add printer”.
2. Believe or not, click “Add a local printer” (I know you want to add a network printer but that way it doesn’t work).
3. Click “Create a new port” - “Local Port” - “Next”
4. In the next box you have to enter a port name like this: \\PC name\Printer name where “PC name” is the network name of the XP PC where you have the printer and “Printer name” the network name of that printer. Be careful with this names - you can double-check by viewing the PC in “Network Places.”
5. Finish the wizard and enjoy your UAC-free network printing!