You’re running a mail server.
I’m running a desktop that should be spending it’s time compiling my apps, not wasting limited resources searching for ills the rest of the world insists on being vulnerable to.
So, no email? Nice gig.
Does your desktop actually post outbound mail to internet mailservers directly? I.E. does it have its own Postfix or Exim or similar mailserver software that connects with port 25 on other mailservers on the internet? Or does it -- as I suspect -- merely have a mail client that sends outbound mail via an SMTP connection on another machine, that is, on an actual mail server?
I'm hoping you'll tell me you use an SMTP service at your ISP, or Google/Yahoo/Apple, or on your corporate network, or something like that.
But if your desktop is your mailserver, I'd say you are foolish because you're talking directly to other internet mailservers with your compiling machine, which is asking for trouble.
Which?