This page contains information on how to identify problems with your installation.


Whilst Postal can verify DNS records on its own, it can be useful to check what the rest of the internet is seeing.

You can make use of Whats My DNS for a quick global check or the dig command if you have it on a terminal, i.e. dig txt or dig a


The quickest way to ensure the internet can connect to your Postal SMTP is with telnet 25. You can proceed to attempt sending a message manually if you are familiar with the raw SMTP commands to further verify your Postal installation is working correctly.


If you aren't sure about whether the SSL certificate you have provided to Postal is set up correctly you can use openssl s_client -connect -starttls smtp to get some information about your certificate from the point of view of SMTP.