Index: core/kernel/db/db_event_handler.php
===================================================================
--- core/kernel/db/db_event_handler.php
+++ core/kernel/db/db_event_handler.php
@@ -1730,7 +1730,9 @@
 				$table_info = $object->getLinkedInfo();
 			}
 
-			$object->SetDBField($table_info['ForeignKey'], $table_info['ParentId']);
+			if ( $table_info !== false ) {
+				$object->SetDBField($table_info['ForeignKey'], $table_info['ParentId']);
+			}
 
 			$event->redirect = false;
 		}