WPF Richtextbox - ScrollBarVisibility is giving exception while opening the WPF window second time

Hi,

I am getting the exception "Cannot use a DependencyObject that belongs to a different thread than its parent Freezable." while opening (second time on words) WPF window having RichTextBox with VerticalScrollBarVisibility property.

If I remove the property it works, but i have to show the vertical scroll bar.

Using VS 2010 professional with .Net 4.0 framework and Operating System is Window7 .

Here is the Window "Window1.xaml" having RichTextBox which loads "abc.rtf" file

Opening the Window as followed

Thread newSettingsWindowThread;

ParameterizedThreadStart p = new ParameterizedThreadStart(ShowWindowThreadStart);
            newSettingsWindowThread = null;
            try
            {
                newSettingsWindowThread = new Thread(p);
                newSettingsWindowThread.SetApartmentState(ApartmentState.STA);
                newSettingsWindowThread.IsBackground = true;
                newSettingsWindowThread.Start(params);
            }
            catch (Exception )
            {   }

private void ShowWindowThreadStart(object inParams)
{
Thread.CurrentThread.Name = "New WindowThread";

              var WinObj = new Window1();
              WinObj .WindowStartupLocation = WindowStartupLocation.CenterScreen;
              WinObj .Topmost = true;
              WinObj .Closed += (sender, e) => WinObj .Dispatcher.InvokeShutdown();
              WinObj .Show();

System.Windows.Threading.Dispatcher.Run();

}

Very first time, the window can be seen and can be closed. Second time onwards the issue is there.

If I remove the property "VerticalScrollBarVisibility" it works fine.

Please help me to figure it out the issue, is it really related to that property or any thing internally causing the issue.

Thanks in advance.