Why isn't my auto-versioning in my winforms app not incrementing?

I have a simple winforms app for testing auto-versioning which I specified in the AssemlyInfo.cs file under properties. How do I make it increment?

// You can specify all the values or you can default the Build and Revision Numbers
// by using the '*' as shown below:
[assembly: AssemblyVersion("1.0.*")]
//[assembly: AssemblyVersion("1.0.0.0")]
[assembly: AssemblyFileVersion("1.0.0.0")]

winform:

private void Form1_Load(object sender, EventArgs e)
{
    lblMessage.Text = Class1.HelloTest();


    string version = System.Windows.Forms.Application.ProductVersion;
    this.Text = String.Format("My Application Version {0}", version);
}