Today many of our customers around the world and the critical systems they depend on were victims of malicious "WannaCrypt" software. Seeing businesses and individuals affected by cyberattacks, such as the ones reported today, was painful. Microsoft worked throughout the day to ensure we understood the attack and were taking all possible actions to protect our customers. This blog spells out the steps every individual and business should take to stay protected. Additionally, we are taking the highly unusual step of providing a security update for all customers to protect Windows platforms that are in custom support only, including Windows XP, Windows 8, and Windows Server 2003. Customers running Windows 10 were not targeted by the attack today.

Details are below: Read more.