I am using Microsoft.Office.interop.Excel version 14.0. I see a lot off questions about which XlFileFormat you have to use for creating a Excel 2010 file. So my question is which XlFileFormat should i use to create a Excel 2013 file?
Use
xlOpenXMLWorkbook
or
xlOpenXMLWorkbookMacroEnabled
These are compatible with Office 2013
See full list at: https://msdn.microsoft.com/en-us/library/microsoft.office.interop.excel.xlfileformat.aspx