Add-Edit: Exact Match
By default, words included in the Policies Keyword List and anti-spam rules are considered a match if the specified word matches any part of the message text.
For example, if "Free" is specified in the Keyword list, an occurrence of "Freezer" in the message text is considered a valid match. Or, if "aol" is specified in the spam filter's Routing domain or To: fields, then all email addresses from aol.com and all email routed via aol.com SMTP servers are considered matches.
To prevent such generalizations and reduce the likelihood of false positives, put a check in the Exact Match box of the appropriate spam filter Add/Edit rule field, or in the content filter's global setting: Use exact matches only checkbox. It is also a good idea to avoid very short rules or keywords, such as "aol".
With exact matches enabled, only when the total number and order of letters in the two words being compared are the same, is a match valid. In other words, only when "Free" is found to be exactly equal to "Free" (not "Freezer") is the match valid.
Accepting partial words as a valid match can increase the incidents of false positives. Because in the case of content filtering this value applies to all Policies, every Keyword used in each list for each policy is considered for partials. It is recommended that you enable Use exact matches only for content filtering.
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