Error of limit of memory in your website
S.A. to execute your website you have an error of memory similar to this:
Fatal error: Allowed memory size of xxxxx bytes exhausted
You can try to place following in the file .htaccess in the root of your website:
php_value memory_limit 128M
Also it you can do in the file php.ini if you have access to modify it.
If with that it is not solved, you will have to contact to the administrator of your hosting to ask to them what is the limit assigned to script PHP in the servant.