Increase your settings. The more aggressive the filter setting, the fewer spam messages will reach your inbox. Please note that more aggressive the setting, the more often you should visit the Message Center to confirm that legitimate messages are not quarantined. If they are, add those senders or domains to your Approved Sender list.

Review your Approved Mailing List. Do you have other email addresses forwarding to this account? Check to be sure your addresses are NOT on the Approved Mailing List

Forward your spam. Participate in keeping the filters accurate by sending your unfiltered spam messages AS ATTACHMENTS in email to spam@postini.com. This does not guarantee that these messages will be filtered in the future, but will make it more likely.

"NOTE:   To forward the email as an attachment, highlight the email that you feel is spam and then click on "Message" at the top of your email program.  That should drop down a number of options.  One of those options is: "Forward as an Attachment".  Just click on that and it will open up a new email with that email already set as an attachment.  (attaching the email retains all of the original information as to where it came from so Postini can track it back.)"