Most new e-mail clients include their own basic form of antispam or Junk Mail filtering. Microsoft Outlook 2003 comes with a fairly comprehensive Junk E-Mail filter that gives you some control over how your mail is managed.

To access the filter options, open Outlook and go to Actions > Junk E-Mail > Junk E-Mail Options. From this dialog box you can manage how Outlook responds to incoming e-mails. The first tab, Options , instructs Outlook as to how sensitive spam detection should be. There are actually only two levels of sensitivity, the remaining two options allowing the filter to be turned off or configured for preapproved senders only.

It's generally a good idea to start off with sensitivity set to Low , because it's easier to mark spam that the filter misses than to locate legitimate e-mails in a folder full of spam.

At the bottom of the dialog box is a checkbox labelled Permanently delete suspected junk e-mail. You should never check this because Outlook can occasionally determine a legitimate e-mail to be false positive spam e-mail; if it's deleted permanently, you'll never even know it was incorrectly detected. This becomes important when you begin to train the filtering system.

The remaining tabs in the Junk E-mail Options dialog are self-explanatory, and allow you to configure e-mail addresses that either should always be let through the filter, or should always be blocked.

After enabling the Junk E-mail filter, Outlook begins to detect spam. Initially, you may find that some legitimate e-mails are being flagged as spam, so you need to tell Outlook what it has done wrong.
Simply open the legitimate e-mail and select Actions > Junk E-mail > Mark as Not Junk . Outlook then modifies its spam detection rules accordingly.