Problem setting up printer for AirPort Extreme wireless printing

I have an AirPort Extreme 802.11n and I've connected my Canon MP240 printer to it via USB. However, my MacBook Pro (running OS X 10.8.4) says the printer is "offline" when it is plugged into AirPort Extreme and turned on. When I try to add it as a new printer, it recognizes it as a "Nearby Printer" and asks me to download and install the software from Apple. It then searches for the software for about a minute and gives me this error message: "Can't install the software for the Canon MP240 series because it is not currently available from the Software Update server." I've tried directly downloading the drivers from Apple's website http://support.apple.com/kb/DL899 and from Canon's website http://www.usa.canon.com/cusa/support/consumer/printers_multifunction/pixma_mp_s eries/pixma_mp240#DriversAndSoftware but neither work.

HOWEVER, the strangest part is if I were to connect the printer to my MacBook Pro directly via USB, it recognizes the printer and I can print no problem. This leads me to believe the drivers have already been installed onto my computer. If anyone knows how to get around this issue I'd greatly appreciate the help.