- Go to Tools menu > Message Filters.
- Click New to create a new filtering rule.
- Enter spam as the new filter name.
- Create a new header entry which is used to filter spam messages. To do this, select Customize... from the first drop-down list.
- Enter X-Spam-Flag as the new message header and click Add. Click OK to close the Customize Headers dialog box.
- Create a rule that when X-Spam-Flag contains Yes, the message is moved to the spam folder. To do this, select X-Spam-Flag from the first pull-down menu, contains from the second and enter Yes as the text you want to match.
- Check Move to folder check box from Perform these actions list.
- Select the spam folder from the Move to folder pull-down menu.
- Click OK to confirm your new spam filtering rule.
- Close the Message Filters dialog box.