Access to these features requires you to log in to SmarterMail (http://mail.yourdomain.com) using the administrative account, refer to your setup email. 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 Domain Settings icon (last icon in the top navigation - looks like 9 dots when not active)
Step 2: Click the Spam Filtering option in the left pane
Step 3: Make the required changes and click Save
For more details on all the SmarterMail features click your User Icon on the top right (colored letter button) inside your web mail control panel and select Open the Online Help to access the comprehensive knowledge base included with your web mail application.