Rather than deleting the printer definition, try creating a second definition to the same printer, and testing with that. If you delete the last printer of a particular type, the drivers get deleted and need to be reloaded. (Sometimes this is a goodthing, but make sure you have the CD.)
If the printer is from HP, first try printing a status report on it from its console. This will show the IP address (if any) and the network status. You can also use the HP Directjet utility to query the printer status.
Maybe it is just Spring, but I have had a plague of users kicking out network connections lately. Check the printer's network line (both ends). Check also, if it goes through a hub, that the power has not been pulled from the hub. (I had a user do this last week.)
You can easily check network printer connections by pulling the network line out of the printer and plugging it into a laptop. If the laptop can hit the network, you can eliminate all network hardware as causes of the problem.
Once you have physical connectivity, if you cannot ping the printer, the problem may be in the printer's network hardware. Power off the printer and re-seat the card if possible. You will probably have to reconfigure the IP address if you do this.
Good luck.
