The STN_ENABLE notification message is sent when a static control is enabled. The static control must have the SS_NOTIFY style to receive this notification message. The parent window of the control receives this notification message through the WM_COMMAND message.
STN_ENABLE
idStatic = (int) LOWORD(wParam); // identifier of static control
hwndStatic = (HWND) LOWORD(lParam); // handle of static control