Qpopper runs under xinetd by default. Are you sure it is running? You can make it run in server mode by recompiling it using ./configure --enable-standalone Other than command line options when you compile, there are no other configuration files to mess with. Your pop server just listens on its port and when a request comes in, it matches the user name and password and gets the file from /var/spool/mail/username and sends it to the client. If you need special handling or filters, that is done via the local mailer (procmail).