Do you trust your spam filter?|
Spam filters have to be trained. The way you do that is by inspecting your spam queue now and then, and rescuing messages that were erroneously marked as spam.
To do that, select (checkbox) the message that you want to rescue. Then click the "Not Spam" button that appears at the top of the page. That should move it back to your inbox AND notify the spam AI that it made a mistake.