With the increase in usage of email, many users receive a number of unwanted and unsolicited commercial email messages that are known as spam. Not only does spam make it difficult to identify valid email messages, but some spam contains offensive messages and images. The Web Query is a feature of Norton AntiSpam that Norton Internet Security uses to classify the email messages more effectively.

An effective spam filtration is possible when each email message that you receive is scanned through different filters. With only one or two levels of email filters, a high percentage of legitimate emails is misclassified as spam or spam is misclassified as legitimate. To avoid such misclassification, Norton AntiSpam employs different filters. Each email filter uses a unique approach to filter spam email messages from legitimate email messages.

The email messages that you receive in your email program undergo scanning through different local filters of Norton AntiSpam. The local filters use Whitelist technique, Blacklist technique, and patented filtering technology to classify email messages as legitimate or spam. If the local filters classify an email message as spam, Norton AntiSpam changes the subject of the email message. Norton AntiSpam then sends the email message to your email client. However, if the filters classify the email message as legitimate, Norton AntiSpam collects information such as signature and URL hashes of the email message. Norton AntiSpam then sends this information to the Web Query filter for additional scrutiny.

The Web Query filter analyzes the signature and URL hashes of the email message and then sends the analysis report to Norton AntiSpam. If the email message is identified as spam, Norton AntiSpam alters the subject of the email message and sends it to your email program. Based on predefined email rules, the email program then moves the email message to the Junk folder or the Norton AntiSpam folder.