Microsoft has three versions of the Server Message Block (SMB) protocol. The first version has the least security and should be disabled or removed immediately. The second version of SMB was introduced with Vista and Windows Server 2008, and the third came along with Windows 8 and Server 2012. These two later SMB versions should not be disabled permanently, since they are used for a variety of network-based activities such as supporting file sharing, encryption, large MTU packets and messages. Now is also a good time to review your network isolation policies, such as virtual private networks.”]