This menu option turns the filter on or off. The filter indexes your messages and lets you find a message that Spam Sleuth might have missed, or that you were expecting.
Each time you use the filter, the program will index the messages that have not yet been indexed. If the index it too out-of-date, the entire set of messages will be re-indexed.
Tip: If you leave the filter on, and the Find: fields are blank, you will see all of your messages, but the messages will be indexed as they come in. This is useful if you use the Filter feature often and would like to keep the index current.
If you want more control over the searching, you can use the Advanced Filter which gives you more control, but you need to use the syntax of the search language. See Appendix B for more information on the Advanced Filter Syntax.