I am running both a VISTA machine and some XP Pro machines and there is a difference in setup. Make sure either way you connect the printer to each machine first and install the drivers. From an XP machine, run the setup wizard and make sure you force an IP for the print server. Saves a lot of headache I think rather relying on DHCP and letting the Print server figure it out. On the XP machine, run the Install wizard for each computer next and you should be good to go. On the Vista machine, manually edit the port to match the IP of the printer. You may need to create a new port first and then delete the old one afterward. This got me up and running with no issues.