Apache "localhost is currently unable to handle this request." php request

Question

I'm using Apache 2.4 server on my laptop running under Windows 10. I’m having a problem running a piece of php code which is supposed to show random numbers for users to tap in, so that we know that this user is not a robot. Below is a picture shows what I’m talking about: The numbers have yellow background is what I'm referring.

So, the code that I have for generating these number is as follows:

<?php
/**
    USAGE:
	<img alt="" rel="nofollow,noindex" width="50" height="18" src="php/captcha.php" />
	$_SESSION['captcha']  - use it in your script.

	Supported link:
		util/captcha.php?w=100&amp;h=50&amp;s=30&amp;bgcolor=ffffff&amp;txtcolor=000000
**/
	session_start();
	@ini_set('display_errors', 0);
	@ini_set('track_errors', 0);

	header('Cache-Control: no-cache');
	header('Pragma: no-cache');


/** ********************************** 
 @RANDOM GENERATORS [LN, N, L]
/** ******************************* **/
    function random($length=6,$type=null) { // null = letters+numbers, L = letters, N = numbers

		switch($type) {
			case 'N' :	$chars = '0123456789'; 								break;
			case 'L' :	$chars = 'abcdefghijklmnopqrstuvwxyz'; 				break;
			default  :	$chars = 'abcdefghijklmnopqrstuvwxyz0123456789'; 	break;
		}

		$numChars = strlen($chars); $string = '';
        for ($i = 0; $i < $length; $i++) { $string .= substr($chars, rand(1, $numChars) - 1, 1); }
		unset($chars);
		return $string; 
	}


/** ********************************** 
 @_GET shortcut and protect
/** ******************************* **/
	function _getVar($var) {
		if(isset($_GET[$var])) {
			return trim($_GET[$var]);
		} else { return null; }
	}


/** ********************************** 
 @CAPTCHA
/** ******************************* **/
	// Put the code in session to use in script
	if(_getVar('c') != '') 
		$c = (int) _getVar('c'); 
	else 
		$c = 6;
	$mycode = random($c,'N');
	
	$_SESSION['captcha'] = $mycode;

	// Image Size from a specified dimensions
	$w =  (int) _getVar('w'); if($w == '') $w = 60; // width
	$h =  (int) _getVar('h'); if($h == '') $h = 18; // height
	$s =  (int) _getVar('s'); if($s == '') $s = 5; // font size [5 max.]
	$bgcolor  = _getVar('bgcolor');  if($bgcolor == '')  $bgcolor   = 'ffffff'; // background color [ffffff default]
	$txtcolor = _getVar('txtcolor'); if($txtcolor == '') $txtcolor  = '000000'; // text color [000000 default]

	// convert color to R  G  B 
	// [from ffffff to  ff ff ff]
	$bgcol 	 = sscanf($bgcolor,  '%2x%2x%2x');
	$txtcol	 = sscanf($txtcolor, '%2x%2x%2x');
	// Create image
	$code  = $_SESSION['captcha'];
	$image = imagecreate($w, $h); 											// image size [50x18 default]
	$bgcol = imagecolorallocate($image, $bgcol[0], $bgcol[1],  $bgcol[2]); 	// background color
	$txcol = imagecolorallocate($image, $txtcol[0], $txtcol[1], $txtcol[2]); // text color
	$strn2 = imagestring($image, $s, 0, 0, $code, $txcol);					// text size [4 default]
	header('Content-Type: image/jpeg');

//    imagepng($image);  // make sure --with-png-dir is set
	imagejpeg($image);
	imagedestroy($image);

?>

When I run this code on Apache, I always get

"The localhost page isn’t working. localhost is currently unable to handle this request. HTTP ERROR 500"

this error. I'm aware this is a server error but it runs OK using my Mac OX operating system which has Apache pre-installed. But this code get the above error on if I use Windows 10 which I have Apache and PHP installed as instructed on Youtube.

Can anyone help?? Thanks in advance!

Solution

That is telling you that Apache cant find native error page 500. You have an error in your PHP code, change display_errors to 1 and add this next to that error_reporting(-1);