public static string MyAddress( [Parameter("x")] double x ) { XL._Application theApp = ExcelInstance.Instance(); XL.Range range = (XL.Range)theApp.get_Caller(System.Type.Missing); return(range.get_Address(System.Type.Missing, System.Type.Missing, XL.XlReferenceStyle.xlA1, System.Type.Missing, System.Type.Missing)); }