STARTTLS cannot be enforced. It will be used automatically if the mail server supports it. The encryption type should be grup to ‘None/STARTTLS’ in this case. See here for an example on how to configure self signed certificates. DuckDuckGo’s homepage is similar to Google’s, except that there is only one https://wikimapia.org/external_link?url=https://www.autofreshshop.com/