Hi David!
I believe it was in version 11.x that this option was removed; however, it was soon re-added in version 12.0.5157. You'll need to upgrade your installation to see it. It looks like your license is valid for 14.x, so you'll just need to follow the steps here:
Major Upgrade of SmarterMail.
Andrea Free
SmarterTools Inc.
877-357-6278
www.smartertools.com