Obviously I don’t run a boot-scan, or any other virus scan, on a daily basis. I noticed the problem when I did a boot scan as part of the false rootkit cleanup, which Avast asks the user to do. Once I managed to get back the wireless network, I carefully tried to find out by elimination why I lost it in the first place. It’s the antivirus, not the firewall (Kerio, which plays nice with everything, for the benefit of the mindless sloganeering right-winger), or anything else.