Assembly: Microsoft.Office.Interop.Excel (in microsoft.office.interop.excel.dll)
Only 2-D stacked bar or column chart groups can have series lines. This object isn’t a collection. There’s no object that represents a single series line; you either have series lines turned on for all points in a chart group or you have them turned off.
Use the SeriesLines property to return a SeriesLines object.
If the HasSeriesLines property is False, most properties of the SeriesLines object are disabled.