protected override void WndProc(ref Message m) { base.WndProc(ref m); if ((m.Msg != WM_SYSCOMMAND) || ((int)m.WParam != SYSMENU_CONFIG_ID)) { return; } if (app.proc != null && app.proc.IsRunning) { return; } var config_dialog = new FormConfig(); config_dialog.ShowDialog(this); if (TextBoxOutput.Text.Trim() == String.Empty && AppConfig.OutputDirectory.Trim() != String.Empty) { TextBoxOutput.Text = AppConfig.OutputDirectory + @"\output.mp4"; } }