WinApi Group Box problem

[chubakueno]

I have read http://bytes.com/topic/c/answers/891582-radio-button-groupbox-not-generating-wm_command but when I try:

hwndFrame = CreateWindow(
		"BUTTON",
		"Test",
		WS_CHILD | WS_VISIBLE | BS_GROUPBOX | WS_CLIPCHILDREN,
		304,
		112,
		233,
		63,
		hwnd,
		NULL,
		g_hInst,
		0);
	if(hwndFrame == NULL) return 0;
	hwndBtnCerrar = CreateWindow(
		"BUTTON",
		"Close",
		WS_CHILD|WS_VISIBLE|WS_TABSTOP,
		20,
		20,
		103,
		17,
		hwndFrame,
		(HMENU)IDBTNCERRAR,
		g_hInst,
		0);
	if (hwndBtnClose == NULL) return 0;
	
	GroupBoxProc = (WNDPROC)GetWindowLongPtr(hwndFrame, GWLP_WNDPROC);
	SetWindowLongPtr(hwndFrame, GWLP_WNDPROC, (LONG_PTR)(GroupRelay));

The button works fine, but I the problem it's that is was all in vain because the frame doesn't appear, so how could I do to see the Group Box and enable the "Close" button? Any help would be appreciated