I just recently blocked all incoming traffic(all local ports and all external ips) in my windows 7 firewall and I understand that will not stop me from accessing websites as browsing needs outbound connection. That was fine with me.
However, though I'm not able to access any shared files or rdp to this computer from local networks, I find I can VOIP or chat in Internet. I wonder how it's possible.
According to my understanding, to send messages we need incoming ports open which I have blocked then why I can still chat or VOIP.