When I playe ye olde Freelancer, I couldn't find any servers toplay online (the official ones are gone but there are user-created ones). But now I've got two Steam games (Killing Floor and Left 4 Dead 2), and neither of those work online (KF won't find any games, L4D2 finds a game but can't connect to it). It turns out, at least in KF's case (haven't tried it on L4D2), that this is because of Look 'n' Stop - I can play if I don't have Look 'n' Stop loaded. So how do I play online without having viruses and malware attack me? EDIT: Steam says "Look 'n' Stop has been reported to cause issues with Steam when its "Unknown UDP Packet" filter is enabled". Where can I disable it and does this put me at risk?