php - PHP_excel: Export to xlsx gets downloaded successfully but when we open it it shows warning Excel found unreadable content

Question

i am using php_excel to export to xlsx. In my application im making use of template. When i download, the xlsx file gets downloaded fine, but when we open its showing the following warning:

"Excel found unreadable content in 'project_report(3).xlsx'. Do you want to recover the contente of this workbook? If you trust the source of this workbook, click Yes."

If i click yes it opens the file correctly.

And one more thing is when i attach the downloaded file to the mail. And if i open it sing Google Spread sheet it says bad format unable to open.

so if anyone know the reason please suggest me to solve this.

Answer 1

check your headers, here are mine:

   header("Pragma: public");
   header("Expires: 0");
   header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
   header("Content-Type: application/force-download");
   header("Content-Type: application/octet-stream");
   header("Content-Type: application/download");;
   header("Content-Disposition: attachment;filename=$filename");
   header("Content-Transfer-Encoding: binary");
   $objWriter->save('php://output');

check for output (spaces before <?php forgotten echo? etc