"postfix? its not installed on my system..."
You could install it
The postfix home page can be found at
http://www.postfix.org/, but you can only download the source and compile it. Compiling software isn't difficult, but it could be a little confusing for newbies. (and the postfix source install is a little rare/odd too, for some reason
)
Fortunately,
www.linuxpackages.net has a nice postfix package for slackware too
(i'll just assume you have slackware
)
* download it
* open a terminal window
* type "su" to become root. (I hope you aren't root already, this is not a good thing)
* type "installpkg postfix..." Just press the tab button to auto-complete.
* type "exit" to leave your root-shell, and exit again to close the window.
Since postfix installs a sendmail compatible interface, you might want to remove sendmail first. Removing a package can be done with "removepkg <name>", but you might want to try the "pkgtool" command. pkgtool displays a nice graphical menu where you can look for the package, and remove it too.
The postfix configuration is stored in /etc/postfix/, and main.cf is the first file you might want to look at. type "postfix start" to start postfix, and "postfix reload" if you change the configuration (or wait a few seconds). Most mail-deamons log infomation in /var/log/maillog; you can view any diagnostic information in that file.