Hi johnbusy,
Please make sure that there is a strong signal between your printer and the wireless access point. To do this, please follow these steps:
1. Click Start and select All programs (or Programs). If you are using OS X, please open the Appliations folder.
2. Click on Canon IJ Network Utilities, Canon IJ Network Tool, and then Canon IJ Network Tool.
3. Select the printer in Printers.
4. Select Status from the View menu.
The Signal Strength indicates the strength of the signal received by the printer, ranging from 0% to 100%.
The Link Quality indicates the signal quality excluding the noise while communicating, ranging from 0% to 100%.
Both of these values should be as close to 100% as possible.
Make sure that there is no barrier or obstacle between the access point and the machine. Wireless communication between different rooms or floors is generally poor. The metal, concrete, or timber including the metallic material, mud wall, or insulator may interrupt a wireless communication. If the machine cannot communicate with the computer over a Wireless LAN for the wall material, place the machine and the computer in the same room or floor.
Since a device such as a microwave oven uses the same frequency bandwidth, it may cause interference. Place the wireless devices as far away from the source of interference as possible.
Also, please log into your router and change the channel in your Wireless Settings. Please try changing the channel to 11 or 6. Changing the channel may eliminate any interference.
Interference can come from Bluetooth devices, cordless phones, microwave ovens and other nearby wireless networks if they are on overlapping channels. Please refer to your routers' documentation for assistance in changing the wireless channel.
Also, routers have a feature that will disconnect devices that have not been in use for a period of time. If you do not use your printer, the router will stop sending wireless signals to it and will become disconnected from the network. Please refer to your routers manual to adjust this time out period or disable it.
If you continue to have difficulties, please contact our support group using the following link:
http://www.usa.canon.com/cusa/consumer/standard_display/contact_us_consumer
