public partial class MyJokesWindow : mmBusinessWindow { private Humor Humor; /// <summary> /// Constructor /// </summary> public MyJokesWindow() { this.Humor = (Humor)this.RegisterBizObj(new Humor()); //this.Window.DataContext = this.Humor.GetMyJokesByPunchline("test"); // the above gives: "Object reference not set to an instance of an object." //this.Window.DataContext = this.Humor.GetAllEntities(); //this.grdMyJokes.ItemsSource = this.Humor.GetMyJokesByPunchline("test"); //and above gives the same error // this.grdMyJokes.ItemsSource = this.Humor.GetAllEntities(); //and above gives the same error this.InitializeComponent(); } }But all the commented out variations of trying to retrieve the entity list above result in the same error: