Intruder alert

Want to be warned when a virus has evaded your virus checker and is infecting your PC? Robert Morris of Lancashire has the answer (GB 2364142). Most viruses propagate by covertly e-mailing copies of themselves to addresses in a computer’s address book. So Morris suggests adding a trap address to the address book: as soon as a virus strikes and sends out e-mails, at least one will go to the trap. The office server, or your Internet service provider, checks mail arriving at the trap address and e-mails you a warning if it finds a virus there. The network can…