SSRS Servers <= 2014 cannot be configured to send email using a password. And in this day and age, what idiot allows their email server to relay unauthenticated email?
If you have any interest in SSRS, please remember where this blog entry is, you'll want it, and it'll save you the days that I've spent on this.
This article will walk you through setting up a mail server on a Server 2012 box with SQL 2014, and then configuring the mail server to only accept connections from the SQL server. This provides the security that we need to be sure that we're not an open relay.
Here we go: