Add the SpamAssassin Anti-SPAM management interface to your Plesk software. Activating this on your license adds an additional Spam filter to your system that is configurable Server-wide or at the domain level.

SpamAssassin is an open source mail filter to identify spam. Using its rule base, it uses a wide range of heuristic tests on mail headers and body text to identify "SPAM".

Spam Assassin Anti-SPAM Support Interface is the Shareware version. The full version can be purchased by clicking on the "CLICK HERE TO ORDER" button below for around 49.00USD.