At my business we have an Exchange 5.0 server. We have a single POP account at our ISP that collects mail for the entire domain. On the Exchange server we run a POP3Exchange program that will at reg intervals download all our mail and send it to the Exchange server for delivery within ut office. Our problem comes when we want to send mail. Our ISP will not let us send mail to their SMTP server without us First logging into our POP account and downloading our email. We have no way to synchronize this on our Exchange server. Also using DNS will not work because we must use their mail server to send mail out to the internet. My question is if we placed a linux box on the network could we get it to do what I am describing (POP before send)and then forward all mail to the exchange server?