Log in to SmarterMail interface for your domain name (http://mail.yourdomain.com) using your full email address and password. If it is your first time using the service the web mail system will ask you to set a time zone before logging in, just select your local time zone and click Save.
Step 1: Click the Settings icon (last icon in the top navigation - looks like 9 dots when not active)
Step 2: From the expanded menu click Settings
Step 3: Click Autoresponder in the left pane
Step 4: Check Enable Autoresponder in the Options tab
Step 5: Create a subject and body for your auto responder
Step 6: Click the Save button near the top
To turn off the auto-responder when it's no longer needed, uncheck the Enable Autoresponder option under the Options tab and click Save.