Mac OS X Mail comes with one of the best spam filters you'll find in any email program. To make it work really excellently for you, you have to help it a bit, though.
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Since the Bayesian-style spam filter of Mac OS X Mail relies on the type of spam as well as the type of good mail that you receive, you should tell it whenever it guesses wrong for a message. This helps to make the filter perform even better.
To help the Mac OS X Mail junk filter identify spam by correcting its decisions:
- If Mac OS X Mail wrongly identifies a message as junk
- click the Not Junk button.
- If Mac OS X Mail doesn't detect a message as spam that definitely is
- click the Junk toolbar button or
- select Message | Mark As Junk Mail from the menu.

