<<< MacOS 10.09 Mavericks
Setting up Mail Relay
When using MacOS as a mail host, you will most likely run into issues with Policy Block Lists (PBL), if like me your server sits behind the IP Address that you ISP’s assigns your then this most likely going to be recorded in the Spamhaus Policy Block List.
The solution is to setup a mail relay in the Mail Services, I use Prolateral which is a UK company that offers a free service that can be used to test the setup before committing to purchase
The issue I discovered is that Mavericks only uses ports 25, for clear text passwords, and 465, for SSL encrypted passwords, whereas most SMTP providers appear to use port 587 for SSL encrypted passwords.
Enter support to help solve the issue: Mavericks uses Postfix as the underlying mail delivery system and so it is possible to edit the underlying configuration files to get this working.
The trick is to change the security options to anonymous, to do that follow the following commands in a command window
$ cd /Library/Server/Mail/Config/postfix
$ sudo vi main.cf
G
smtp_sasl_password_maps = hash:/Library/Server/Mail/Config/postfix/sasl/passwd
smtp_sasl_auth_enable = yes
smtp_sasl_security_options = noanonymous
smtp_sasl_mechanism_filter = plain,login
:x!
This will add the necessary commands to the end of the file and it should all now work, just make sure that you do not change the settings in the server, or you will have to do this again.