SpamAssassin is a mail filter to identify spam using text analysis and several internet-based realtime blacklists. Using its rule base, it uses a wide range of heuristic tests on mail headers and body text to identify ``spam'', also known as unsolicited commercial email. Once identified, the mail is then tagged as spam for later filtering using the user's own mail user-agent application.
For more information, please visit the developers' website: http://www.spamassassin.org
To simply have the server DELETE and NOT deliver emails that are tagged as spam by SpamAssassin, click here. If you have enabled this option and want to cancel it, click here.
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Spam Box
This feature allows emails identified as spam by SpamAssassin to be delivered to a seperate mail folder named "spam". If this folder is not regularly checked and emptied, it may cause your email or filesystem quotas to be exceeded, resulting in a failure to receive legitimate messages. You easily can use IMAP or Horde/IMP to check messages that are routed to this box. If you wish to use pop3 to check the spam box, just add "/spam" (without the quotes) to the end of your pop3 login. (Example: joe@i.com/spam)
This feature's use is generally discouraged in favor of sorting and deleting spam messages using your mail client. Without Spam Box you can configure SpamAssassin to mark your email with an identifying subject (e.g. ***SPAM***), which can then be filtered out into an appropriate location.