New Post: Importing CSV Error

After following the discussion link

http://nbstore.codeplex.com/discussions/81116

I am trying to import products. But after click on Import it shows the error like

System.NullReferenceException: Object reference not set to an instance of an object. at NEvoWeb.Modules.NB_Store.ImportCSV.buildCSVCategoryXML(PortalSettings PS, String[] CSVlines, String FieldDelimeter, String FieldQualifier, String FieldEscapedQualifier) at NEvoWeb.Modules.NB_Store.ImportCSV.ImportCSVProducts(PortalSettings PS, String ImportFile, Boolean UpdateExistingProductsFlg, Boolean CreateCategoriesFlg, String RowDelimeter, String FieldDelimeter, String FieldQualifier, String FieldEscapedQualifier)

After reading lot of discussion on this forum I am unable to get the solution. Please help me to solve this problem.