How does the filter determine what is spam?

The Lightspeed Systems Spam Filter module is a powerful tool that filters out viruses and inappropriate content without hindering your ability to work and communicate. When mail is received it is first scanned for viruses. Next, it is processed according to the spam rules. The first pass is a pre scan that generates a spam score. The second pass processes the email for specific rules, which are performed, in order, for each recipient. Learn more about those rules and steps here.