Canon MX450 series Online Manual page 36

If the firewall function of your security software is turned on, a message may appear warning that
Canon software is attempting to access the network. If the warning message appears, set the security
software to always allow access.
If using any programs that switch the network environment, check their settings. Some programs will
enable a firewall by default.
• Check 12: When using a router, connect the printer and computer to
the LAN side (same network segment).
• Check 13: When the printer is connected to an AirPort Base Station via
a LAN, use alphanumeric characters for the name of the network
(SSID).
If the problem is not resolved, insert the CD-ROM in the DVD/CD-ROM drive on your computer to start
setting up again, or access our web site through the Internet and download the latest MiniMasterSetup for
your model.