private void Browse_Click(object sender, RoutedEventArgs e) { var close = false; using (var openDialog = new OpenFileDialog()) { openDialog.InitializeLifetimeService(); openDialog.Filter = "License files (*.xml)|*.xml|All files (*.*)|*.*"; openDialog.Title = "Select License file"; if (ShowDialogInSTA(openDialog) == System.Windows.Forms.DialogResult.OK) { string licenseFileSelected = openDialog.FileName; if (ValidateLicenseFile(this, licenseFileSelected)) { close = true; } } } if (close) { this.DialogResult = true; this.Close(); var registered = new Registered(); registered.ShowDialog(); } }