Macbook Air can't ping new HP Printer

Ok Confused. Just bought a Macbook Air a couple of weeks ago. It functions correctly even swaping between woreless networks. So bought a new HP 8600 Plus printer (running wireless). Both Win 7 wired (bad words I know) works and prints. Downloaded and installed printer package from HP. Installed it but it can't find the printer. What I have figured out is that the MB Air can't ping the printer. It can ping the hardware 1 octet either side of the printer's IP and the wireless gateway. Printer does ping from the Win 7 devices. IP Firewall not turned on.