Canon PIXMA iX6850 - Manual (Page 255)

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.
Check12 When using a router, connect the printer and computer to the LAN side (same
network segment).
Check13 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, perform setup according to the instructions on our website.
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