It sounds like you are not able to add your Canon printer in System Preferences. I found an article with steps you can take to resolve this:
USB printers and Bonjour-enabled network printers
Follow these steps until the issue is addressed:
- Make sure that the printer is powered on, has ink / toner, and that there are no alerts on the printer’s control panel. Note: If you cannot clear an alert on the printer's control panel, stop here and check the printer's documentation or contact the manufacturer for support.
- Ensure the printer is properly connected to a USB port on the Mac or AirPort base station / Time Capsule. If the printer is a network-capable printer, make sure that it is properly connected to your home network.
- Use Software Update to find and install the latest available updates. If an update is installed, see if the issue persists.
- Open the Print & Scan pane or Print & Fax (Snow Leopard) pane in System Preferences.
- Delete the affected printer, then add the printer again.
If the issue persists, try these additional steps:
You can find the full article here:
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