what's wrong?

[javic]

        Info: COM_VIRTUEMART_ASSIGN_VM_TO_MENU


( ! ) Notice: Trying to get property of non-object in D:\wamp\www\Joomla3\components\com_virtuemart\views\category\view.html.php on line 79
Call Stack
#   Time   Memory   Function   Location
1   0.0010   382280   {main}( )   ..\index.php:0
2   0.2318   7964552   JSite->dispatch( )   ..\index.php:42
3   0.2400   8280680   JComponentHelper::renderComponent( )   ..\application.php:197
4   0.2504   8385320   JComponentHelper::executeComponent( )   ..\helper.php:351
5   0.2512   8472048   require_once( 'D:\wamp\www\Joomla3\components\com_virtuemart\virtuemart.php' )   ..\helper.php:383
6   0.2739   9322720   JController->execute( )   ..\virtuemart.php:100
7   0.2740   9322768   VirtueMartControllerCategory->display( )   ..\controller.php:760
8   0.2740   9323928   JController->display( )   ..\category.php:60
9   0.2795   9594816   VirtuemartViewCategory->display( )   ..\controller.php:721

[javic]

vm 2.0.8e