daknetworks.com

-go to ATT.com.
-Account > Sign in.
-Manage Profile.
-Sign-in info.
-select Manage secure mail keys (at the bottom)
-Add secure mail key.
-type in a nickname for the secure mail key (example: Outlook).
-click Create-Secure-Mail-Key.
-the new secure mail key is shown and should be used for email access in Outlook/Thunderbird/Mail app.