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Modules - Antispam - 3.x

Overview

The antispam software works in conjunction with your mail server. The software identifies spam using a wide range of algorithms on e-mail headers and body text.

Installation

If you did not select this module to be included during the installation process, you must first install the module.

General Options

• Report Type - defines how spam is reported to the end user
• Mail Volume - typical mail volume on your system

An antispam report is generated with every message marked as spam. This report can be hidden in the mail headers, sent in-line (prefixed), or added as an attachment. Here is an example report:

*  1.2 FORGED_HOTMAIL_RCVD2 hotmail.com 'From' address, but no 'Received:'
*  0.1 CLICK_BELOW_CAPS BODY: Asks you to click below (in capital letters)
*  0.0 HTML_40_50 BODY: Message is 40% to 50% HTML
*  0.0 HTML_MESSAGE BODY: HTML included in message
*  2.1 BAYES_80 BODY: Bayesian spam probability is 80 to 95% [score: 0.8163]
*  0.1 HTML_FONT_BIG BODY: HTML tag for a big font size
*  0.2 MIME_HTML_ONLY BODY: Message only has text/html MIME parts

To speed up mail processing, the antispam software pre-loads data into your system's memory. If you set your mail volume settings too high, you will be wasting memory and potentially slowing your system. To optimize memory usage, you can change the mail volume settings on your system. Use the following guidelines:

• Low - 2,000 messages per day
• Medium - 10,000 messages per day
• High - 20,000 messages per day
• Very High - 50,000 messages per day

White and Black Lists

• White List - a list of e-mail addresses that should never be marked as spam
• Black List - a list of e-mail addresses that should always be marked as spam

The antispam engine includes both white and black lists. The white list is used to mark e-mail addresses that send non-spam, while the black list is used to mark e-mail addresses that are known spam.

Among others, newsletters and legitimate e-commerce e-mail can sometimes be marked as spam. The e-mail addresses for these messages can be added to the white list to prevent the message from becoming marked as spam.

E-mail addresses in the white and black lists can use the * wildcard character to match any characters. For instance, *@example.com and *.gov will mark all e-mail from the example.com and .gov domains.

Subject Tag

• Use Subject Tag - enable/disable e-mail subject tag when e-mail is marked as spam
• Subject Tag Threshold - spam score required to trigger a change in the e-mail subject
• Subject Tag - the subject tag to use when e-mail is marked as spam

A subject tag can be added to messages marked as spam. For instance a spam message with the subject "Premier Invest0r Rep0rt" will be transformed into "[SPAM] Premier Invest0r Rep0rt". This feature makes it easy for end users to identify and filter spam.

Quarantine

• Quarantine Score - score required to reach threshold
• Quarantine Action - actions
• Admin E-mail Address - administrator e-mail address (only required if you redirect spam to an administrator)

The antispam system is flexible with handling e-mail. Messages can be:

• Passed through
• Saved to the quarantine
• Sent to an administrator
• Discarded

Links

• SpamAssassin website