The more I get into PF firewall rules, the stranger it gets. First, I an running WIN 7. For starters, observe where the DHCP rules are located in PF. Since XP, DHCP is controlled by svchost.exe but in PF the DHCP rules are located under System Services? If you try to set up the DHCP rules under svchost.exe where they should be, you will get bombarded with outbound udp port 1900 to remote IP 18.104.22.168 messages in your PF firewall log. Appears to me PF has issues with muticast traffic. It also appears to ignore the outbound udp port 1900 default rule PF generates for svchost.exe. Then there are the strange DNS tcp port 53 outbound rules in lsass.exe and services.exe. Lsass.exe is only applicable to domain i.e. office profile and services.exe has not been used since WIN 2000? Finally there are rules missing that are required for WIN 7 Homegroup to function: svchost.exe 1. In/out tcp port 3587 2. In/out udp port 3540 system 1. In tcp port 2869 -WIN mediaplayer networking 2. In/out tcp port 5357-5358 Might explain why people trying to network with PF are having issues.