Microsoft introduces "SmartScreen for URLs" protection mechanism to safeguard users from social engineering attacks exploiting the Windows Live Wave 4 Beta networks.
"SmartScreen is designed to verify the reputation of a link, before user is allowed to actually navigate to a specific website. If the site is legitimate with no history of scams or malware, SmartScreen willn't interfere and will allow users to perform Direct Navigation (Redirection)."
However, it's set up to block navigation "if link points to a known bad website— for e.g., one that hosts malware or phishing scam—the redirection server navigates the user to a red block page," said John Scarrow. At the same time, the SmartScreen filter can present an informal message to customers "if the website has very low traffic or has had a history of abuse, you'll be taken to an informational interstitial page."