Integrated Open Relay check connecting to any external ORB database to ensure the sender is not in blacklisted for sending spam email.
Secure Mail Server has dozens of configuration options to directly block users or servers identified as abusing the mail server. These include banning by sender IP address, recipient mail address, from mail address; limits on number of recipients per email, maximum bad addresses in a row, email per sender IP address and maximum messages to a single mail account.
Gateway Mail Server will integrate with any external command line virus scanner that has the option to delete mail if it contains a virus.
Gateway Mail Server has support built in spam detection. Spam System uses a combination of filter-rules and fuzzy matching to correctly identify over 98% of spam. The spam messages are marked with a header so individual users then choose their own 'level' of spam tolerance.
The Spam system can be customized by each client. The customization base on the spam rating. You can choose to hold*, bounce*, or vanish* a message before you even see it. This setting can be done in web based.
Using elaborate rules, customized policies can be setup for mail forwarding, archiving and filtering. Filtering will typically take some form of action on messages identified as spam by Spam System or external spam identification filters. An alternative use for filtering is to limit mail based on content.
This could allow you to setup policies that
The Friends System allows users to receive messages only from friends. Non friends are automatically questioned to determine if they are human. All mail from non friends is held pending on the Gateway Mail Server until the user decided what to do with it. Status reports are sent to the user on a regular basis to provide information on the Friends system and any mail pending delivery.