I'm running a sendmail 8.11.6 mail server behind a firewall. I allow internal users get mail from the server with POP3 and send messages out with SMTP thru the server. I did this by allowing the local network to relay off the server What I would like to do is allow users from the outside of my firewall to be able to get their messages with POP and be able to send messages thru my sendmail SMTP server. I want to be able to have my remote users to be able to setup POP and SMTP server information in their e-mail client like they would for an ISP. The remote users will have different IP addresses My question, how do I setup my sendmail server to only allow authenticated users to be able to send mail thru my server, and not make the server an open relay. (Like an ISP) I've searched Yahoo and a sendmail book, but I haven't really found what I'm looking for. (I don't know if I've been using the correct terminology, so far i've been looking for things like - client smtp authentication relay ...) Does anyone know how to do what I'm to do, or can point me in the right direction. Thanks for any help Jim Streit