System.ArgumentOutOfRangeException: L'index était hors limites. Il ne doit pas être négatif et doit être inférieur à la taille de la collection.
Nom du paramètre : index
à System.ThrowHelper.ThrowArgumentOutOfRangeException()
à System.Collections.Generic.List`1.get_Item(Int32 index)
à Infragistics.Win.UltraWinSchedule.TimelineView.ActivityPositioningCalculator.CalculateLayout(UltraTimelineView control, List`1 activities, Rectangle containerBounds, Int32& activityAreaScrollPosition, Boolean includeAllActivities, Boolean& hasMoreRows, Dictionary`2& layout, Int32& totalRows, Int32& rowsPerView)
à Infragistics.Win.UltraWinSchedule.TimelineView.ActivityPositioningCalculator.CalculateLayout(UltraTimelineView control, List`1 activities, Rectangle containerBounds, Int32& activityAreaScrollPosition, Boolean& hasMoreRows, Dictionary`2& layout)
à Infragistics.Win.UltraWinSchedule.TimelineView.ActivityAreaUIElement.PositionChildElements()
à Infragistics.Win.UIElement.VerifyChildElements(ControlUIElementBase controlElement, Boolean recursive)
à Infragistics.Win.UIElement.VerifyChildElements(ControlUIElementBase controlElement, Boolean recursive)
à Infragistics.Win.UIElement.VerifyChildElements(ControlUIElementBase controlElement, Boolean recursive)
à Infragistics.Win.UIElement.VerifyChildElements(ControlUIElementBase controlElement, Boolean recursive)
à Infragistics.Win.UIElement.DrawHelper(Graphics graphics, Rectangle invalidRectangle, Boolean doubleBuffer, AlphaBlendMode alphaBlendMode, Boolean clipText, Boolean forceDrawAsFocused, Boolean preventAlphaBlendGraphics)
à Infragistics.Win.ControlUIElementBase.Draw(Graphics graphics, Rectangle invalidRectangle, Boolean doubleBuffer, AlphaBlendMode alphaBlendMode, Size elementSize, Boolean preventAlphaBlendGraphics)
à Infragistics.Win.ControlUIElementBase.Draw(Graphics graphics, Rectangle invalidRectangle, Boolean doubleBuffer, AlphaBlendMode alphaBlendMode)
à Infragistics.Win.UltraControlBase.OnPaint(PaintEventArgs pe)
à Infragistics.Win.UltraWinSchedule.UltraScheduleControlBase.OnPaint(PaintEventArgs pe)
à System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer)
à System.Windows.Forms.Control.WmPaint(Message& m)
à System.Windows.Forms.Control.WndProc(Message& m)
à System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
à System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
à System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

I have this exception when i'm scrolling right or left in the timelineview. is not always fired;

i restart my program and all is OK.

i can't catch this exception in my code... please tell me the way to resolve this.

thx