I get this error message after i get in the first page of my website
Fatal error: Call to undefined method jQuery::loadAllExtensions() in /home/a1808737/public_html/mall_admin/includes/application_top.php on line 355
what’s the matter? Advices are appreciated 
Welcome to Sitepoint. 
That error is stating that the jQuery object, does not have the method loadAllExtensions. I don’t know how OSCommerce works, so I cannot really be of much help here.
Hi Anthony,
Where can I search for a similar code ? Or should I create it myself?
Look for a file with the string ‘jQuery’ in its name, now somehow that file is not being loaded, so you’d need to find out what/where files are included.