Adjust filtering options if you want to filter messages more aggressively, specify what to look for in a message, and specify character sets that you want to block.
You can set the filtering level to control how aggressively you filter email. There are five filtering levels that range from least aggressive to most aggressive. If you find that messages are being handled incorrectly, you can change the level. For example, if spam is not filtered (called false negatives), you can set a more aggressive filtering level. If your legitimate messages are marked as spam (called false positives), you can set a less aggressive filtering level. For the most aggressive filtering, set the level to Restricted, where the only email messages that reach your Inbox are those from senders in your Friends List and those larger than a specified size (spam messages are typically very small). All others are filtered.
Anti-Spam allows you to customize the options for processing spam. You can move spam and phishing email to the Spam folder, and change the default tag that is added to the subject line of each message, which identifies spam (SPAM) and phishing email (PHISH). You can also filter email by the size of a message. Because spam messages are generally small, by default Anti-Spam filters messages smaller than 150 KB.
You can specify how often to update your spam filtering rules. Spam filtering rules are updated automatically to filter your email with the most up-to-date rules. If you have a fast network connection, you can update more frequently for better results.
Anti-Spam can look for specific character sets when it analyzes spam. A character set represents a language, including its alphabet, numerals, and special symbols. If you receive spam in Greek and you do not receive legitimate email in Greek, you can filter all messages that contain the Greek character set.
Be careful not to filter character sets for languages in which you receive legitimate email. For example, if you want to filter messages in Italian and do so by selecting Western European (Italian uses the Western European character set), Anti-Spam filters messages in all languages that use the Western European character set, including English. If you receive legitimate email in English, these messages are filtered as spam.