如何在Windows应用程序中始终使用C#在系统托盘中显示我的应用程序图标

我有Windows应用程序，我希望我的应用程序图标将始终显示在系统托盘中。就像现在一样，它会随着时间的推移而隐藏。请帮助我解决我的问题。提前谢谢。

Code of System tray App: 
NotifyIcon ni = new NotifyIcon();
// Put the icon in the system tray and allow it react to mouse clicks.          
ni.MouseClick += new MouseEventHandler(ni_MouseClick);
ni.Icon = Resources.favicon;
ni.Text = "***";
ni.Visible = true;
// Attach a context menu.
ni.ContextMenuStrip = new ContextMenus().Create(ni);
ni.BalloonTipText = "abc...";
ni.BalloonTipTitle = "abc";
ni.ShowBalloonTip(5000);