Class notifier not found

[14-Sep-2011 03:51:04] PHP Fatal error: Class 'notifier' not found in /home/vinyhaa1/public_html/mailorder/includes/autoload_func.php on line 79

This is the error message i get in the debug log. I can access the admin backend just fine now and seems to be looking fine. But now i cant access the front end of the shopping cart, because i get a 500 error. This is what shows up in the cache debug file.

no clue what it means, or how to fix it.

It sounds like either your /includes/auto_loaders/config.core.php file is corrupt or some of the class files are missing.

You could start by editing /includes/application_top.php to change the line

/**
 * boolean if true the autoloader scripts will be parsed and their output shown. For debugging purposes only.
 */
define('DEBUG_AUTOLOAD', false);

to

/**
 * boolean if true the autoloader scripts will be parsed and their output shown. For debugging purposes only.
 */
define('DEBUG_AUTOLOAD', true);

Make sure to FTP the changes back up to your hosted installation. That debug output should tell you want the culprit is.

Sounds like files might have been missed from your upgrade. http://www.zen-cart.com/forum/showthread.php?t=185934

500 Errors: https://www.zen-cart.com/tutorials/index.php?article=63

Blank pages: https://www.zen-cart.com/tutorials/index.php?article=82