Sent to the window that is losing the mouse capture.
A window receives this message through its WindowProc function.
This parameter is not used.
A handle to the window gaining the mouse capture.
An application should return zero if it processes this message.
A window receives this message even if it calls ReleaseCapture itself. An application should not attempt to set the mouse capture in response to this message.
When it receives this message, a window should redraw itself, if necessary, to reflect the new mouse-capture state.
Minimum supported client
|Windows 2000 Professional [desktop apps only]|
Minimum supported server
|Windows 2000 Server [desktop apps only]|
Build date: 11/16/2013