WPFanimation issue

 hello all,

 here is my sample code 

 <ProgressBar  Orientation="Vertical" Minimum="0" Maximum="100" x:Name="prgTime"
                     Width="50" Height="350" Margin="50" x:Name="prgTime"
                    />

          and in window loaded    

       void MainWindow_Loaded(object sender, RoutedEventArgs e)
        {
            Duration duration = new Duration(TimeSpan.FromSeconds(30));
            DoubleAnimation doubleanimation = new DoubleAnimation(0, 100, duration);
            prgTime.BeginAnimation(ProgressBar.ValueProperty, doubleanimation);
        }

This code works fine in VS 2008 but when i copy paste in VS 2012- it does NOT work.

Am I missing something ?

Pls help

Regards

Durga