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// create a thread
Thread newWindowThread = new Thread(new ThreadStart(() =>
{
// create and show the window
FaxImageLoad obj = new FaxImageLoad(destination);
obj.Show();
// start the Dispatcher processing
System.Windows.Threading.Dispatcher.Run();
}));
// set the apartment state
newWindowThread.SetApartmentState(ApartmentState.STA);
// make the thread a background thread
newWindowThread.IsBackground = true;
// start the thread
newWindowThread.Start();