Fatal error: Uncaught Error: Class 'Tinebase_Model_Filter_FilterGroup' not found in /home/compute1/public_html/tine.computerfee-server.de/Inventory/Model/InventoryItemFilter.php:19 Stack trace: #0 {main} thrown in /home/compute1/public_html/tine.computerfee-server.de/Inventory/Model/InventoryItemFilter.php on line 19