Salut,
Le message WM_
CTLCOLORBTN ne permet pas de changer la couleur des boutons normaux. C'est précisé dans MSDN : << Buttons with the BS_PUSHBUTTON, BS_DEFPUSHBUTTON, or BS_PUSHLIKE styles
do not use the returned brush. Buttons with these styles are always
drawn with the default system colors. Drawing push buttons requires
several different brushes-face, highlight and shadow-but the
WM_CTLCOLORBTN
message allows only one brush to be returned. To provide a custom
appearance for push buttons, use an owner-drawn-button. >>.
Voici un code source montrant comment changer la couleur des boutons (entre autres) :
http://www.cppfrance.com/codes/COULEURS_ET_TRANSPARENCE_DES_CONTROLES_-API-/27889.aspx