Magento 500 Internal Server Error

Often times, when a Magento 500 Internal Server Error happens is when you use the Magento admin to create backups, for instance when you are installing a new extension and it hangs up.

What the issue here is a function in lib/Mage/Archive/Helper/File.php line 102 on Magento CE 1.9.1.0

public function open($mode = 'w+', $chmod = 0666)

and in lib/Mage/System/Dirs.php

public static function mkdirStrict($path, $recursive = true, $mode = 0777)

This can be found Stackoverflow Question

But if you have a Magento 500 Internal Server Error, that’s what we need to fix first.

First thing is not to worry, not all is lost. Second, download and unzip magento-cleanup.zip place this php file in root directory of your installation, or copy and paste the code below in a new php file in the root and name it magento-cleanup.php You can also download the exact same file from Here

<?php

## Function to set file permissions to 0644 and folder permissions to 0755

function AllDirChmod( $dir = "./", $dirModes = 0755, $fileModes = 0644 ){
   $d = new RecursiveDirectoryIterator( $dir );
   foreach( new RecursiveIteratorIterator( $d, 1 ) as $path ){
      if( $path->isDir() ) chmod( $path, $dirModes );
      else if( is_file( $path ) ) chmod( $path, $fileModes );
  }
}

## Function to clean out the contents of specified directory

function cleandir($dir) {

    if ($handle = opendir($dir)) {
        while (false !== ($file = readdir($handle))) {
            if ($file != '.' && $file != '..' && is_file($dir.'/'.$file)) {
                if (unlink($dir.'/'.$file)) { }
                else { echo $dir . '/' . $file . ' (file) NOT deleted!<br />'; }
            }
            else if ($file != '.' && $file != '..' && is_dir($dir.'/'.$file)) {
                cleandir($dir.'/'.$file);
                if (rmdir($dir.'/'.$file)) { }
                else { echo $dir . '/' . $file . ' (directory) NOT deleted!<br />'; }
            }
        }
        closedir($handle);
    }

}

function isDirEmpty($dir){
     return (($files = @scandir($dir)) && count($files) <= 2);
}

echo "----------------------- CLEANUP START -------------------------<br/>";
$start = (float) array_sum(explode(' ',microtime()));
echo "<br/>*************** SETTING PERMISSIONS ***************<br/>";
echo "Setting all folder permissions to 755<br/>";
echo "Setting all file permissions to 644<br/>";
AllDirChmod( "." );
echo "Setting pear permissions to 550<br/>";
chmod("pear", 550);

echo "<br/>****************** CLEARING CACHE ******************<br/>";

if (file_exists("var/cache")) {
    echo "Clearing var/cache<br/>";
    cleandir("var/cache");
}

if (file_exists("var/session")) {
    echo "Clearing var/session<br/>";
    cleandir("var/session");
}

if (file_exists("var/minifycache")) {
    echo "Clearing var/minifycache<br/>";
    cleandir("var/minifycache");
}

if (file_exists("downloader/pearlib/cache")) {
    echo "Clearing downloader/pearlib/cache<br/>";
    cleandir("downloader/pearlib/cache");
}

if (file_exists("downloader/pearlib/download")) {
    echo "Clearing downloader/pearlib/download<br/>";
    cleandir("downloader/pearlib/download");
}

if (file_exists("downloader/pearlib/pear.ini")) {
    echo "Removing downloader/pearlib/pear.ini<br/>";
    unlink ("downloader/pearlib/pear.ini");
}

echo "<br/>************** CHECKING FOR EXTENSIONS ***********<br/>";
If (!isDirEmpty("app/code/local/")) { 
    echo "-= WARNING =- Overrides or extensions exist in the app/code/local folder<br/>";
}
If (!isDirEmpty("app/code/community/")) { 
    echo "-= WARNING =- Overrides or extensions exist in the app/code/community folder<br/>";
}
$end = (float) array_sum(explode(' ',microtime()));
echo "<br/>------------------- CLEANUP COMPLETED in:". sprintf("%.4f", ($end-$start))." seconds ------------------<br/>";
?>

Next, navigate to www.yourwebsite.com/magento-cleanup.php the script will automatically run and change all file and directory permissions for you.

Refresh your website page, and things should be back to normal again, please delete this file from your server.

To prevent a Magento 500 Internal Server Error from happening in the future, you can change the lines mentioned at the beginning of the article, and keep this file handy.

Hope this helps someone, cheers.