I seems that you pay very little attention to my posts.

I already told you that to make sure STunnel starts up with Windows that there is an entry in the STunnel program folder to install Stunnel as a service that will automatically start with Windows.

No, I do not have those dll files in my system32 folder.

This post shows what is happening, even though it mentions GMail the principle is exactly the same for your AT&T account.

http://forum.avast.com/index.php?topic=23814.msg201231#msg201231

STunnel is managing the secure connections to your server and then passing the email messages to OE on a regular connection so that avast can scan them. The transfer takes place entirely inside your computer so the messages are still safe from interception.