Ext not defined VirtueMart

I’ve installed VirtueMart on one of my websites, when I opened the VirtueMart Control Panel in my Joomla! Administration Panel I noticed that when the view is set to Simple Layout all the tabs “Accordion Menu” are extended and I get the following JavaScript error: Ext not defined and most functionality that includes JavaScript is disabled. When I click on Extended Layout the problem is solved.

Solution:

To solve this problem we need to disable the usefetchscript function that VirtueMart uses

Open the /administrator/components/com_virtuemart/virtuemart.cfg.php file and add the following line

$_REQUEST['usefetchscript'] = "0";

above the line

global $mosConfig_absolute_path,$mosConfig_live_site;

and save your changes.

Refresh the VirtueMart Administration Panel and the problem will be solved.