New Post: Error opening file, generated by Excel5

Hi. I have code that gererates the file in excel2007 format.
I need to generate file in excel2003 format. This how i do it
$objWriter = PHPExcel_IOFactory::createWriter($e, 'Excel2007');
$objWriter2003 = PHPExcel_IOFactory::createWriter($e, 'Excel5');
$objWriter->save($_SERVER["DOCUMENT_ROOT"].'/upload/pricelist_autogenetate/price'.$priceID.'.xlsx');
$objWriter2003->save($_SERVER["DOCUMENT_ROOT"].'/upload/pricelist_autogenetate/price'.$priceID.'.xls');

But, when i open excel2003 file, excel says "the file is corrupted"

How can i fix it?