I'm having the same problem with Windows 7 and the HP8500 office jet A810. I can communicate with the printer, I recently changed the IP address and the updated IP address showed up immediately in the printer properties. I'm on a KVM switch with an XP machine which has no problem communicating with the printer.
In order to install the 8500 its necessary to use the installation disk. It's not a simple matters of downloading a driver and updating. The smallest intallation media (downloadable) is something like 80meg. The biggest one is 220meg. These include ann the HP favorites like "Shopping".
I saw it suggested somewhere else that it may be a firewall problem but haven't figured that one out yet.
Edited by hamluis, 01 March 2012 - 02:39 PM.
PM sent new OP.