Could not connect to SMTP host: email-smtp.us-east-1.amazonaws.com, port: 465, response: -1

Question

I am trying to send email with Amazon\'s SES/SMTP and I am getting the following error:

javax.mail.MessagingException: Could not connect to SMTP host: em

Answer 1

This employee from AWS states that SES does not support SSL at all. https://forums.aws.amazon.com/message.jspa?messageID=218303 .

Amazon SES will attempt to send email with Transport Layer Security enabled, but there is not a way to guarantee messages are sent with TLS. SES uses opportunistic TLS when sending emails, which means it will attempt to send emails over TLS first, and then will fall back to regular SMTP if TLS is unavailable.

Hence, I am thinking the issue you are seeing is not TLS or SSL related, rather something else.