protected override void OnStartup(StartupEventArgs e) { //System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo("en-US"); //System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("en-US"); SingleInstance si = new SingleInstance(appGuid); si.ArgsRecieved += (args) => (this.MainWindow as MainWindow).HandleCommandLineArgs(args); si.Run(() => { var win = new MainWindow(); win.Loaded += (sender, args) => win.HandleCommandLineArgs(e.Args); win.Show(); return this.MainWindow; }, e.Args); }