Sets the background color of the button when it is in the Disabled state.
If this color is left undefined, the current colors settings are kept.
This property is ignored when the Surface property is set to SURFACE_VISTA_AERO, SURFACE_OFFICE_2003, SURFACE_OFFICE_2007 and no special effect has been set through the SpecialEffect property.
This property encapsulates the functionality of the SurfaceColor object and the ISurfaceColor COM interface.
For further details about colors change, see the How to change the button colors section.