Update: Thread to be closed. I have found answer in manual and by collecting info regarding all affected ports. After installation of v3 I have figured out that a lot of IP packets is passed through nod32. Packets generated by 3rd party applications. nod32 should be interested in those packets directly, apart from scanning for vulnerabilities. E.g.: while connecting from winamp to online radio stations, http, port 8000 or similar. Winamp itself is sending request to 127.0.01:30606. After that nod32 is sending packets to external addresses with ports 8000, 8050. My firewall doesn't have any filter rule meeting this traffic. So I have opened port 8000, 8050 but then nod32 doesn't use those. Instead of this it uses some others. And the packets don't still are passed to external world. What's wrong. Does nod32 really have to pass these packets ? How many ports do I have to open in this case to get it working ? I don't want a huge hole.