A WM_PAINT case is necessary in order to draw the current client-area text on the screen when the window has been minimized, resized, or overlaid. Add the following case to the window procedure:
case WM_PAINT:
hDC = BeginPaint (hWnd, &ps);
if (hText != NULL) {
if (!(lpszText = GlobalLock (hText))) {
OutOfMemory();
} else {
GetClientRect (hWnd, &rectClient);
DrawText (hDC, lpszText, -1, &rectClient
, DT_EXTERNALLEADING | DT_NOPREFIX | DT_WORDBREAK);
GlobalUnlock (hText);
}
}
EndPaint (hWnd, &ps);
break;