Apache "localhost is currently unable to handle this request." php request
<p>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:
<a href="http://i.stack.imgur.com/6Rq3s.png" rel="nofollow">The numbers have yellow background is what I'm referring.</a></p>

<p>So, the code that I have for generating these number is as follows:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;?php
/**
    USAGE:
 &lt;img alt="" rel="nofollow,noindex" width="50" height="18" src="php/captcha.php" /&gt;
 $_SESSION['captcha']  - use it in your script.

 Supported link:
  util/captcha.php?w=100&amp;amp;h=50&amp;amp;s=30&amp;amp;bgcolor=ffffff&amp;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 &lt; $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);

?&gt;</code></pre>
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</p>

<p>When I run this code on Apache, I always get </p>

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

<p>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.</p>

<p>Can anyone help?? Thanks in advance!</p>