Windows 10 Sep 2019 Update, version 1903 (codenamed 19H1) is the seventh major refresh of the OS (after its original release), and it’s the first semi-annual update of 2019. This new update delivers a new set of features and enhancements to improve performance, security, and it helps users be more productive. Starting with version 1903, Windows 10 is adding an acrylic effect, part of Fluent Design, to the sign-in background. The translucent texture helps you focus on the login task by moving the actionable controls up in the visual hierarchy while maintaining their accessibility. You can also download Windows 8.1 Pro ISO October 2019.