Hi infragisticsMaster,

In my preliminary tests, it looks like the auto-scrolling behavior is internal to the control and only activates when used in conjunction with itself or another XamDataTree.  You can still replicate this behavior, however, by modifying the scroll value depending on the mouse position on the tree.  This code would be placed inside your DragOver/MouseMove event for the XamDataTree.

const double scrollRegion = 20;
Point pt = e.GetPosition(xamDataTree1);

// This check is for the bottom portion of the tree.
if (pt.Y > xamDataTree1.ActualHeight - scrollRegion)
{
 // Store the current scroll value.
 IProvideScrollInfo scrollInfo = xamDataTree1 as IProvideScrollInfo;
 double lastScrollValue = scrollInfo.VerticalScrollBar.Value;

 // Reset the data source so scroll value is taken into account.
 xamDataTree1.ItemsSource = null;
 xamDataTree1.ItemsSource = boundDataSource;

 // The scroll value got reset to 0 so restore it.
 scrollInfo.VerticalScrollBar.Value = (lastScrollValue + 1);
}
// This check is for the top portion of the tree.
else if (pt.Y < scrollRegion)
{
 // Store the current scroll value.
 IProvideScrollInfo scrollInfo = xamDataTree1 as IProvideScrollInfo;
 double lastScrollValue = scrollInfo.VerticalScrollBar.Value;

 // Reset the data source so scroll value is taken into account.
 xamDataTree1.ItemsSource = null;
 xamDataTree1.ItemsSource = boundDataSource;

 // The scroll value got reset to 0 so restore it.
 scrollInfo.VerticalScrollBar.Value = (lastScrollValue - 1);
}

How are you handling the drag and drop?  Are you using our Drag and Drop framework or the default Microsoft implementation with System.Windows.DragDrop.DoDragDrop()?