As others say, to change the icon in the title bar, you must change the icon of labview.exe (if in development mode) or the executable resulting (if built in app). You can achieve this using different methods, as Icon editors and LabVIEW app builder (if version 5.1 or later). If you want to totally remove the icon in the title bar you can create a transparent icon and apply it to your application, the problem is that the app itself will have the transparent icon.