public App()
        {
...
            this.Startup += this.Application_Startup;
            this.CheckAndDownloadUpdateCompleted += new CheckAndDownloadUpdateCompletedEventHandler(Application_CheckAndDownloadUpdateCompleted);
...
            InitializeComponent();
        }
        private void Application_Startup(object sender, StartupEventArgs e)
        {
            if (Application.Current.IsRunningOutOfBrowser) {
                this.CheckAndDownloadUpdateAsync();
            } else {
                StartApplication();
            }
        }
        private void Application_CheckAndDownloadUpdateCompleted(object sender, CheckAndDownloadUpdateCompletedEventArgs e)
        {
            if (e.UpdateAvailable) {
                MessageBox.Show("Необходимо перезапустить программу, ввиду полученных обновлений.");
            } else {
                StartApplication();
            }
        }