Microsoft beefs up the Malicious Software Removal Tool (MSRT) that ships with its Windows operating system. Srizbi was effectively knocked out of action last November when operators of the McColo Internet service provider in San Jose, California, were kicked off the Internet. Microsoft’s detection software runs on hundreds of millions of computers worldwide, including many that are not running up-to-date antivirus software, a move like this can bring a botnet to its knees. Only about 1 percent of the botnet is still active.”]
Source: https://www.csoonline.com/article/2123744/microsoft-update-targets-spam-spewing-botnet.html