When you send an email and it goes to the smtp server, that
server then tries to connect to the mail exchange for the
domain which the email is going to.
Will it connect to this mail exchange from port 25, or will
it open another unpriveledged port? I'm just wondering
whether I can set a firewall option to only allow connections
to the smtp server if it comes from port 25.
Using Debian/GNU Linux
It said 'Required Windows XP or better.'
So I installed Linux.