GFI MailEssentials has a powerful content filtering engine which can block emails by matching keywords found in the email body or subject. This video explains how you can create keyword filtering rules.
To configure keyword filtering rules go to the GFI MailEssentials configuration, Content Filtering and Keyword Filtering. Here you will see a list of keyword filtering rules that can be enabled or disabled.
To create a new rule click on the Add Rule button:
Once added select the rule and click on Enable Selected. A number of attachment filtering rules are available by default and these block racial content, vulgar language and sexual content. All you have to do is enable the filters you want to use and you’re all set to go