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Elsewhere on the Web • Solution 14638 • Real-Life Spam Solutions

Antivirus firm Trend Micro unwittingly targeted the letter "P" with a recent rules update, forcing all email containing the objectionable letter into quarantine. According to their knowledge base article titled Solution 14638, "Antispam Rule 915 unintentionally blocks some legitimate emails scanned by InterScan eManager and ScanMail eManager." The cause? The letter P.

According to Trend Micro, the problem affects their Internet gateway, email and groupware products, including InterScan Messaging Security Suite, InterScan eManager, ScanMail for Exchange, ScanMail eManager, and ScanMail for Lotus Notes. A spokesman for Trend Micro declined to comment on the issue, stating only that "we've notified customers and resellers." According to Internet Week, much of that contact was done via email. One can only imagine the difficulty of composing an email describing the nature of the problem while simultaneously avoiding the use of the letter P.

In his November 2002 article, Langa Letter: Real-Life Spam Solutions, Fred Langa notes that "pattern-matching is notorious for its false positives." Langa anecdotally provides two real-life examples of pattern matching gone bad, one involving a six letter word embedded in "chardonnay" and the second involving England's Essex county. He notes, "These pattern-matching errors may seem funny when related this way, but it's no joke when you find that some vital (and totally innocuous) E-mail has been eaten by a content-oriented filter." Langa's article provides a wealth of information regarding improved spam prevention measures as well as descriptions of various solutions on the market and their associated pros and cons. Or in Trend Micro's case, would that be *ros and cons?

Trend Micro advises that the unfortunate P mishap can be resolved by updating to Antispam Rule 916 or later. Several of their products include options to resend emails erroneously quarantined by the filtering rules. Their Knowledge Base article Solution 14638 contains links to the support solutions for these products.