This was back in Windows XP era. Since Windows Vista came out, Windows Firewall is very capable packet filtering firewall that can filter outbound connections too. With your logic, a process could inject into an existing process and listen for incoming connections too. Then, Windows Firewall is not good for blocking inbound connections neither. This will be my last reply to your comments, as I think this discussion is not constructive and mostly, not related to WFC. You have your own ideas which are very different from mine, I do not want to convince you of anything. You are free to believe anything you want.