whenever i try to access my store, since last night, i get a 404 error page. i contacted the server and they pointed out a PHP error. this is the email i got from their support team:

"Looking at the link and your error log I'm seeing a PHP error:

PHP Fatal error: Cannot instantiate non-existent class: notifier in /var/www/vhosts/leeharveyroswell.com/httpdocs/zen_cart/includes/autoload_func.php on line 79

The first time I see one of those errors is on 10/04 and I see that the index.php in /var/www/vhosts/leeharveyroswell.com/httpdocs/zen_cart was modified on that same date.Did you make any changes then?

Also the link http://www.leeharveyroswell.com/zen_cart/ is redirecting you to http://www.leeharveyroswell.com/zen_...tall/index.php and the directory zc_install doesn't exist."
so it looks like it's trying to reinstall for some reason. i don't think i made any changes that would cause that but i can't be entirely sure. it can't find the zc_install folder is because i threw it away after i finished the installation. i'm a graphic designer, not primarily a web designer, and definitely not a programmer. i'm only just now learning how to use PHP. can anyone help?