Sorry, I wasn't clear with my instructions. It looks like there was a misunderstanding about what I meant by command window. I was referring to the DOS command window that you run from windows.
Here is a link to a writeup on using it. Can you try the ping of the printer IP address again?
Is the printer on a wired or wireless LAN? This really shouldn't matter as it works for the desktop, I just like to know what I'm dealing with.