Question

According to Enable and Control DWM Composition:

Note As of Windows 8, the information in this section is no longer
valid. DWM can no longer be programmatically disabled, nor is it
disabled when an application attempts to draw to the primary display
surface. The following information applies to only Windows 7 and
earlier systems.

OK. So we can no longer programmatically disable DWM. But can it still be disabled? Will pfEnabled of DwmIsCompositionEnabled always be set to TRUE on Windows 8?

If composition can be disabled somehow, is DwmIsCompositionEnabled still somewhat useful in any manner?

Answer 1

According to Desktop Window Manager is always on (Windows) on MSDN:

In Windows 8, Desktop Window Manager (DWM) is always ON and cannot be
disabled by end users and apps.

In Windows 8, DWM desktop composition is a core operating system
component and cannot be disabled. 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.

All of the options for disabling desktop composition that exist in
Window 7 are removed

Apps cannot use DwmEnableComposition to disable desktop composition.
In order to maintain backward compatibility, a call to this API will
return success; however, desktop composition is not disabled

Well, there’s a pretty definitive answer. I’m somewhat curious what the "with a few exceptions" refers to, though… please add a comment if you happen to know. 🙂