User guide

U S E R G U I D E
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4. Anti-Spam analyzes a message to check if it contains strings from the list of blocked phrases or the list of
obscene words. Whenever words from these lists are found in a message, their weighting coefficients are
summed up. If the total of coefficients exceeds 100, such message will receive the spam status. This step is
skipped by default.
5. If the message text contains an address included in the database of phishing or suspicious web addresses, the
message receives the Spam status.
6. E-mail is analyzed using heuristic rules. If the analysis finds in a message signs typical of spam, the probability
of it being spam increases.
7. E-mail is analyzed using the GSG technology. While doing it, Anti-Spam analyzes images attached to the email
message. If the analysis finds in them signs typical of spam, the probability of the message being spam
increases.
8. The application analyzes e-mail attachments in .rtf format. It scans attached documents checking them for the
presence of spam signs. Once the analysis is complete, Anti-Spam calculates how much the probability of the
message being spam increased. The technology is disabled by default.
9. It checks for the presence of the additional features typical of spam. Each detected feature increases the
probability that the message being scanned is in fact spam.
10. If Anti-Spam was trained, the message will be scanned using iBayes technology. The self-training iBayes
algorithm calculates the probability of a message being spam based on the frequency of phrases typical of
spam found in message text.
Message analysis determines the probability of its being spam expressed as the spam rate value. The Spam or Probable
spam status will be assigned to a message depending upon the specified threshold values of the spam rate (see section
"Regulating threshold values of spam rate" on page 108). The product adds by default to the Subject field of spam and
potential spam messages the label [!! SPAM] or [?? Probable Spam] (see section "Adding a label to the message
subject" on page 109). Then each message will be processed in accordance with your rules defined for e-mail clients
(see section "Configuring spam processing by mail clients" on page 111).
IN THIS SECTION:
Enabling and disabling Anti-Spam .................................................................................................................................. 99
Changing and restoring security level ............................................................................................................................. 99
Training Anti-Spam ......................................................................................................................................................... 99
Scanning links in messages .......................................................................................................................................... 102
Detecting spam by phrases and addresses. Creating lists ............................................................................................ 103
Regulating threshold values of spam rate ..................................................................................................................... 108
Using additional spam filtering features......................................................................................................................... 108
Selecting the spam recognition algorithm...................................................................................................................... 109
Adding a label to the message subject .......................................................................................................................... 109
Filtering email messages at the server. Mail Dispatcher ............................................................................................... 110
Excluding Microsoft Exchange Server messages from the scan ................................................................................... 110
Configuring spam processing by mail clients ................................................................................................................ 111