How the SmartScreen Filter works

Internet Explorer's SmartScreen Filter takes a three-pronged approach to detecting phishing scams. First, SmartScreen analyzes sites you visit for tactics commonly used by phishing sites. If it finds suspicious content, SmartScreen displays a warning message and gives you the opportunity to provide feedback.

Second, SmartScreen sends URLs of sites you visit to a Microsoft database of reported phishing sites to catch them before you get there. If you are trying to visit a site that is listed in the database, SmartScreen blocks the site and shows the red warning page described previously. This page offers you the option of ignoring the warning and visiting the page, but that's generally a bad idea. Third, SmartScreen checks downloaded files against the same dynamic database, and if SmartScreen finds a match, it blocks the download and displays a warning message.

Most of the time when SmartScreen reports a suspicious Web site, it's correct. Occasionally, you might see a false positive, meaning that a legitimate site is marked as suspicious. The SmartScreen page offers a link that will open a page on one of Microsoft's Web sites that you can use to report that you believe the site is safe.