See http://forums.comodo.com/index.php/topic,1125.0.html

>I have 3 computers connected to a Linksys router. Prior to yesterday all three appeared to be on the same network. That is, I could see them in My Networking places. Then I installed firewall, Comodo, on two computers. Now none of the computers "see" each other. I am not sure if firewall is the cause as I can't find anywhere in the firewall that it is blocking the network.
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>How do you I try to connect one computer to the other? I did it so long ago I forgot the steps.
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