We have a few different ways you can fight spam:
1. You can adjust the Required Hits values from the myCP -> Email Admin -> your-domain.com -> Spam Setting -> Required Hits page. Lowering the Spam Tag and Spam Drop values will cause Spam Assassin to filter your email more aggressively. Keep in mind this may lead to false-positives if a legitimate sender’s mail is not properly configured or if the content of their message has too many characteristics of a spam email. If the values are set too low, a message might be dropped entirely. An example could be if a legitmate sales or marketing firm you’re working with sends you a mail with an example of a new promotional flyer or webpage in the content of the email itself, would be very likely to trip the spam filter if the values are set too tightly.
2. You can add the domain or email address that is spamming you to your Black List. Once a domain or email address has been added to your Black List, additional email from the domain/email address will be blocked. You can access your Black List by visiting the myCP -> Email Admin -> your-domaincom -> Spam Setting page. If the spam seems to be coming from the same address or domain (firstname.lastname@example.org and email@example.com), simply blocking the entire domain is often the surest way to prevent further messages from that particular spammer.
3. You can create a mail filter that filters out email if one or more conditions is met. For example, you could configure your filter to reject all messages that contain “stock tips” or “cheap drugs”. To setup a mail filter, visit the myCP -> Email Admin -> Users -> Mail Filter page.
If you create more than one filter, please be sure to check the “and continue filtering” option or only the first filter you created will be applied.
You can find more information on making adjustments to spam filtering here.