Fatal error: Uncaught Error: Call to undefined method Mage_Catalog_Model_Resource_Category_Flat_Collection::getAllIdsSql() in /var/domains/haardenexp-haardenexpert.nl/public_html/app/code/core/Mage/Catalog/Model/Resource/Category/Tree.php:295 Stack trace: #0 /var/domains/haardenexp-haardenexpert.nl/public_html/app/code/core/Mage/Catalog/Model/Resource/Category/Tree.php(242): Mage_Catalog_Model_Resource_Category_Tree->_getInactiveItemIds(Object(Mage_Catalog_Model_Resource_Category_Flat_Collection), '1') #1 /var/domains/haardenexp-haardenexpert.nl/public_html/app/code/core/Mage/Catalog/Model/Resource/Category/Tree.php(154): Mage_Catalog_Model_Resource_Category_Tree->_getDisabledIds(Object(Mage_Catalog_Model_Resource_Category_Flat_Collection)) #2 /var/domains/haardenexp-haardenexpert.nl/public_html/app/code/core/Mage/Catalog/Model/Resource/Category.php(576): Mage_Catalog_Model_Resource_Category_Tree->addCollectionData(Object(Mage_Catalog_Model_Resource_Category_Flat_Collection), false, Array, true, true) #3 /var/domains/haar in /var/domains/haardenexp-haardenexpert.nl/public_html/app/code/core/Mage/Catalog/Model/Resource/Category/Tree.php on line 295