As one of my readers has asked: I am using Norton AntiVirus (only £20 and far too important to leave to freeware) and the XP firewall. Not sure how best to configure the firewall so I just left it to the defaults. Everything still works, but then the door may be wide open for the bad people too. I used to administer a corporate firewall as part of my job but all that knowledge seems to have slipped away in the intervening years.....