Problem with running your own mail server now is the big 3 do not trust your email by default
Try setting your mail server up on a dedicated server using a functional IP address (I.E. not one that is sat in the "Residential use" only blacklists belonging to Spamhaus).
Set up your mail server, insuring your DKIM and SPF records are correctly set up and your using properly signed certificates for TLS and try sending an innocent text based email to Yahoo, Gmail or Outlook/Hotmail. It's an absolute guarantee that if they have never seen mail coming from that address before, your email will go straight to the junk folder and will continue to do so for a very long time until they decide (At their own schedule) you are playing nice.
Trying to solve this problem is an absolute nightmare for a lot of people.