I am able to connect to my Dovecot server and read emails. However I am currently doing it using the "PLAIN" password connection. How can I setup postfix and dovecot to use TLS? From what I recall you have to pay for a SSL certificate, is TLS similar or can I do this with some configuration settings minus the money?
There are a couple of alternatives to paying for an SSL certificate:
Either way, once you've got a certificate (and the associated private key), it's a fairly simple matter of setting a few config variables and maybe opening a couple of ports. Rather than rewriting all that here, I'll just point you to the relevant docs: