SBS4.5 I've not needed to use pop3 mail collection until 2 people got HP Jornada 720's. Picking up their mail using pop3 on a dial-up connection is no problem, but they can only send mail to people on the Global Address List - any other addresses bounce back with a "the recipient name is not recognized" message. So I set up a PC directly connected to the network to use pop3 and got the same thing. I've had a trawl through Microsoft's Knowledge Base and the FAQ's on this site and am no wiser, so I'm hoping someone here can offer some help or advice. (I have checked that the username and alias are identical and that the default SMTP address in Exchange is the same as the return address in the pop3 client)