Despite Microsoft's aggressive efforts to get everyone to upgrade to Windows 10 by mid-2018, the company says it is unlikely to meet its self-imposed deadline. In a statement to ZDNet, the company said: Windows 10 is off to the hottest start in history with over 350M monthly active devices, with record customer satisfaction and engagement. We're pleased with our progress to date, but due to the focusing of our phone hardware business, it will take longer than FY18 for us to reach our goal of 1 billion monthly active devices. In the year ahead, we are excited about usage growth coming from commercial deployments and new devices -- and increasing customer delight with Windows. ZDNet's Mary Jo Foley writes: Microsoft Windows and Devices chief Terry Myerson made the original claim at Build 2015, noting that the 1 billion figure would encompass all kinds of devices that would run Windows 10 in some variant, including desktops, PCs, laptops, tablets, Windows Phones, Xbox One gaming consoles, Surface Hub conferencing systems, HoloLens augmented reality glasses and various Internet of Things (IoT) devices. Officials said at that time that the majority of those 1 billion devices would be PCs and tablets. But Windows Phones running Windows 10 Mobile also were expected to help Microsoft reach that total by mid-2018.Since April 2015, the bottom has fallen out of the Windows Phone market, with Microsoft officials conceding that Windows Phone isn't much of a focus for Microsoft in calendar 2016.