Comment by steelframe

I used to run my own mail server, and that very nearly cost me a career-changing job at Microsoft. My reply to a hiring manager for a team I really wanted to work on went into Microsoft's bit bucket because (I'm guessing) their spam detectors didn't like my own domain and my own instance of Exim sending out my emails. When a recruiter (thankfully) followed up and scheduled me for on-site interviews, that manager mentioned that he never got a reply when he emailed me. That was the point where I realized that email had gone the way of fiefdoms, and if I wanted really important emails to make it through, I'd need to choose which castle I wanted to handle my email.