SMTP error: Must issue a STARTTLS command first

Sorry. I know how frustrating that can be.

It’s possible. It does some stuff to try to debug what the issue is, so it may be that the logic it’s using is broken for your case…

There is also a rake task that likely would have been a better bet for you.

    rake emails:test[]

Were you following Troubleshooting email on a new Discourse install?