This file cannot be found when exporting the PHPExcel file.

This file cannot be found when exporting the PHPExcel file! Environment: freeBSD server, PHP + MySQL problem: an excel export function is provided. there is no problem in both windows and Linux testing environments. the file cannot be found on freeBSD online. This file cannot be found when the PHPcode PHPExcel file is exported!
Environment: freeBSD server, PHP + MySQL
Problem: An excel export function is provided, and there is no problem in both windows and Linux testing environments. freeBSD cannot find this file online.

PHP code

          $file_name = isset($_GET['exam_caption']) && !empty($_GET['exam_caption']) ?   $_GET['exam_caption'] : time().mt_rand(1000, 9999);        $outputFileName = iconv ( 'UTF-8', 'gb2312', $file_name . '.xlsx' );        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/vnd.ms-excel' );        header ( 'Content-Type:application/octet-stream' );        header ( 'Content-Type:application/download' );        header ( 'Content-Disposition:attachment;filename=' . $outputFileName );        header ( 'Content-Transfer-Encoding:binary' );        $objWriter->save ( 'php://output' );

Tutorial expert !!!!

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Print out Lu Jin to see it! If the relative path does not work, change the absolute path!
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No log. how can I call it?