With a few exceptions, desktop composition is always on it’s started before the user logon and remains active for the duration of a session. In Windows 8, DWM desktop composition is a core operating system component and cannot be disabled. In Windows Vista and Windows 7, desktop composition is disabled in a number of scenarios. In addition desktop composition is responsible for composing the new Start menu as well as additional window animations that form the core personality of the new Windows operating system. Since desktop composition is responsible for managing all app windows, disabling desktop composition can result in unexpected behavior. Management, separation and protection of the experience with Windows Store appsĭWM desktop composition enables separation and protection of desktop app windows from the new Windows Store app windows by managing and separating the desktop app windows from the Windows Store app windows. In addition, developers don’t need to write and maintain multiple code paths, thereby simplifying development.ĭWM desktop composition supports rendering and presentation of windowed and full-screen stereoscopic 3D app content.

Users of Windows Classic and high contrast themes can use the experiences enabled by desktop composition such as Windows Flip, automatic scaling for high resolution (DPI) scaling, thumbnail previews, and full screen magnifier. With Windows 8, desktop composition is enabled for all themes. In addition, in these earlier versions of Windows, app developers must write and maintain multiple code paths – one where desktop composition is enabled and another where desktop composition is disabled. Hence users of Windows Classic and high contrast themes cannot use experiences enabled by desktop composition such as Windows Flip, automatic scaling for high resolution (DPI) scaling, thumbnail Preview and full screen magnifier. In Windows Vista and Windows 7, desktop composition is enabled only with the AERO Glass Theme. In addition to experiences enabled in Windows 7, now DWM desktop composition enables desktop composition for all themes, support for Stereoscopic 3D, and management, separation, and protection of the experience with Windows Store apps. As in Windows 7, DWM is used to compose the desktop. In Windows 8, Desktop Window Manager (DWM) is always ON and cannot be disabled by end users and apps. Servers – Windows Server 2012 Description

Desktop window manager