private static bool IsClassRegistered()
        {
            // Get instance handle
            IntPtr instance = Marshal.GetHINSTANCE(typeof(MessageWindow).Module);

            // Set class name
            string class_name = "WSUtilWindow";

            // Set up struct
            User.WNDCLASSEX window_class = new User.WNDCLASSEX { cbSize = (uint)Marshal.SizeOf(typeof(User.WNDCLASSEX)) };

            // Return if class exists
            return User.GetClassInfoEx(instance,class_name,ref window_class);
        }
        private static void RegisterClass()
        {
            // Set up struct
            User.WNDCLASSEX window_class = new User.WNDCLASSEX();

            window_class.cbSize = (uint)Marshal.SizeOf(typeof(User.WNDCLASSEX));
            window_class.style = User.ClassStyles.None;
            window_class.lpfnWndProc = new User.WindowProc(User.DefWindowProc);
            window_class.cbClsExtra = 0;
            window_class.cbWndExtra = 0;
            window_class.hInstance = Marshal.GetHINSTANCE(typeof(MessageWindow).Module);
            window_class.hIcon = IntPtr.Zero;
            window_class.hIconSm = IntPtr.Zero;
            window_class.lpszMenuName = String.Empty;
            window_class.lpszClassName = "WSUtilWindow";

            // Register class
            if (User.RegisterClassEx(ref window_class) == 0) throw new Exception("Could not register class.");
        }