Okay, new multifunction. My fiance set up the network, and I can print wirelessly. No problem. He has put it in my hands to set up the scanner function. Problems. When I connect my computer by ethernet cable to the router (also connected to the MX850), everything works as it should. When I disconnect the ethernet, the scanner doesn't recognize my computer, and the computer says that the scanner is not connected. Am I wrong in thinking that the scanner should scan wirelessly? I can't find any information on this problem from anyone else. 
Thanks for any help!
Thanks for any help!