Bob McAdams wrote:
It has been connected via wifi for years, then all of a sudden my system does not even show the printer in the Add Printer window. I've tried to reconnect via the printer with no luck. I think this problem started when I upgraded to OS 10.9 but I don't know if that led to the problem. Another issue is the HP scanner software no longer works. I suspect that HP decided to discontinue support on the printer. I'm thinking I will no longer support HP, and will buy another brand in the future.
My question should of read "Have you check the Printer that it is still connected to your WiFi router"? In the diagnostic report you posted it said WiFi (Wireless) DISABLED.

Until you check that the printer is still connected to your WiFi you can't assume it is a Mac OS X problem. OS X can't connect to a network printer, either by WiFi or Ethernet, if that printer is Not connected to the same Local area network.
You have to go to the printer and find out why the WiFi system on the printer is disabled. Whether it is a setting or the WiFi chip has failed.