Easiest way to have a program minimize itself to the system tray using .NET 4

Example in MSDN forum

Here's a quick example to show how to minimize to the notification area. You need to add references to the System.Window.Forms and System.Drawing assemblies.

public partial class Window1 : System.Windows.Window{    public Window1()    {        InitializeComponent();        System.Windows.Forms.NotifyIcon ni = new System.Windows.Forms.NotifyIcon();        ni.Icon = new System.Drawing.Icon("Main.ico");        ni.Visible = true;        ni.DoubleClick +=             delegate(object sender, EventArgs args)            {                this.Show();                this.WindowState = WindowState.Normal;            };    }    protected override void OnStateChanged(EventArgs e)    {        if (WindowState == System.Windows.WindowState.Minimized)            this.Hide();        base.OnStateChanged(e);    }}

I've had success using this free notify-icon implementation in WPF.

http://www.hardcodet.net/projects/wpf-notifyicon

It's pretty simple to setup and the source code is provided. It doesn't rely on Windows Forms, so it's 'pure' WPF and very customizable.

You can find a tutorial on how to use it on CodeProject.
And here is the Nuget Package

Add notifyIcon to your App from Toolbox.
Select your main form >> go to the Properties >> select Events icon >> under FromClosing event type MainForm_FormClosing >> hit enter.

In opened .cs file enter following event action:

private void MainForm_FormClosing(object sender, FormClosingEventArgs e){     this.Hide();     notifyIcon.Visible = true;     ShowInTaskbar = false;     e.Cancel = true;}

Now your main FORM window will be minimized to the system tray when you click on X button. Next step is to get FORM back to normal state.
Go to the Properties of your notifyIcon >> find DoubleClick event >> type NotifyIcon_DoubleClick and hit enter to get event function created for you.

Put this code to your event:

private void NotifyIcon_DoubleClick(object sender, EventArgs e){    this.Show();    notifyIcon.Visible = false;}

Now, if you want to make the notify icon in fancy style you can add context menu and link it to your notify icon, so you get something like that:

Here is where you link contextMenuStrip to NotifyIcon:

Good luck!