Practicing safe browsing habits, such as using a web browser with built-in safety features and paying attention to alerts and warnings encountered while browsing, is one of the most important steps Internet users can take to protect themselves from malicious software (malware).1 Nevertheless, it can sometimes be difficult for even experienced Internet users to avoid coming into contact with malware. The cybercriminals who publish and distribute malware devote significant effort to convincing or tricking Internet users into clicking links that lead to malware, or that download malicious attachments or applications. Even familiar and trusted websites can sometimes be exploited by attackers to distribute malware using tactics such as drive-by downloads. (See page 78 for more information about drive-by downloads.)
An antivirus or antimalware product that offers real-time protection is one of the most crucial defenses a computer user has against these and other malware distribution tactics. Unfortunately, many computers are not protected by real-time antimalware software, either because no such software has been installed, because it has expired, or because it has been disabled intentionally by the user or secretly by malware. New data analyzed by Microsoft reveals the magnitude of the additional risk that such computers and their users face: in the second half of 2012, computers that did not have real-time antimalware protection were more than 5 times as likely to be infected with malware and potentially unwanted software as computers that did have protection.