The Microsoft Windows Malicious Software Removal Tool checks computers for infections by specific, prevalent malicious software—including Blaster, Sasser, and Mydoom—and helps remove any infection found. When the detection and removal process is complete, the tool displays a report describing the outcome, including which, if any, malicious software was detected and removed. Microsoft releases an updated version of this tool on the second Tuesday of each month, and as needed to respond to security incidents. The tool is available from Microsoft Update, Windows Update and the Microsoft Download Center.
This tool is not a replacement for an anti-virus product. To help protect your computer, you should use an anti-virus product. To have the newest versions automatically delivered and installed as soon as they are released, set the Automatic Updates feature to Automatic. The version of this tool delivered by Windows Update runs on your computer once a month, in the background. If an infection is found, the tool will display a status report the next time you start your computer. If you would like to run this tool more than once a month, run the version that is available from this Web page or use the version on the Malicious Software Removal Tool Web site.