I installed Debian Sarge on my network as proxy server now this machine is working as a proxy very well. Our client need local mail server I would like to plan uses this proxy server as a local mail server. In our network all client machine are windows XP so we would like to use local mail through outlook mail client. I think sendmail and dovecot can solve this problem so I just installed sendmail and dovecot and try to send mails through outlook but it's not working. I think I have to modify sendmail and dovecot configuration files. How I can fix this problem. Please help me.