Hello,

Every once and a while on a screen refresh, my UltraWinChart will throw the following error.

System.NullReferenceException: Object reference not set to an instance of an object.
   at Infragistics.Win.UltraWinChart.IGWinTooltip.AddToControlsCollection(Control controlToAttachTo)
   at Infragistics.Win.UltraWinChart.IGWinTooltip.topLevel_Paint(Object sender, PaintEventArgs e)
   at System.Windows.Forms.PaintEventHandler.Invoke(Object sender, PaintEventArgs e)
   at System.Windows.Forms.Control.OnPaint(PaintEventArgs e)
   at System.Windows.Forms.Form.OnPaint(PaintEventArgs e)
   at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer, Boolean disposeEventArgs)
   at System.Windows.Forms.Control.WmPaint(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at System.Windows.Forms.ContainerControl.WndProc(Message& m)
   at System.Windows.Forms.Form.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Does anyone have an idea why this might happen?

VS 2008 Professional, .Net 3.5 runtime, Infragistics v8.1

Thanks for any information.