Networked printer does not appear

In this office we have four computers and one occasional laptop connected to the network.This is setup with a switch that connects every device that runs on the network.The problem I have is that every other computer in the office can connect to this printer via the IP address.When I try to add this printer it does not recoagnise the port I have specified (which works on the other PCs).The printer is a HP Deskjet 810c (drivers are installed correctly).
Does anyone have any idea why this is? and how I can fix it?