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Modules - Antispam

[edit] 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. ClarkConnect also includes Greylisting and additional Blacklists -- both are effective tools that can be used to detect spam.

[edit] Installation

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

[edit] Configuration

[edit] Version 3.x

Configuration help for version 3.x is here

[edit] Discard Policy (Block Policy)

If you want to discard spam before it reaches mailboxes, you can configure the mail discard policy. For example, you can discard spam marked with high probability (or higher) by using this tool.

[edit] 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.

[edit] Image Processing (OCR)

Enabling Image Processing will improve the spam identification rate for spam messages containing images. Using OCR (Optical Character Recognition), antispam engine will convert images to text and perform analysis on the word content of the image.

[edit] 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.

[edit] Improving Effectiveness

[edit] Spam Training

You can improve the effectiveness of the antispam engine by following these instructions.

[edit] Greylisting and Blacklists

ClarkConnect also includes Greylisting and additional Blacklists -- both are effective tools that can be used to detect spam.

[edit] Links

• SpamAssassin website