Arghh! Bitten by Bill! I decided to put a USB-WiFi network adaptor on my server for those odd occasions when it's useful - Win2K server (of course) demanded a re-boot (and the crowd did not say "Bo Selecta"!) - all the other NICs were now not bound to any protocols. Since that machine lives in a bay in the basement and I access it over VNC & remote desktop I had to dig it out and hose it up in the dining room - it took pulling out the NICs, deleting the driver files and re-installing them before I could get either in LAN adaptor or the Internet facing card to bind to TCP/IP. I took the opportunity to upgrade it to gigabit - BUT, a couple of hours later I thought "I wonder if Windows re-enabled NetBIOS on the Internet facing interface?" AND IT HAD! In two hours I had picked up seventeen worms and assorted other malware.
Now I'm not a Microsoft basher but I wonder why it has taken ten years of people hooking up Windows machines to the Internet for XP SP2 to actually have a safe configuration as default? I'm a geek and know how networking works - I pity people who aren't as in to it as me when they attached to always-on connections.