Fatal error: Uncaught InvalidArgumentException: Constant name is expected. in /var/www/web22/htdocs/lib/internal/Magento/Framework/Data/Argument/Interpreter/Constant.php:23 Stack trace: #0 /var/www/web22/htdocs/lib/internal/Magento/Framework/App/Arguments/ArgumentInterpreter.php(35): Magento\Framework\Data\Argument\Interpreter\Constant->evaluate(Array) #1 /var/www/web22/htdocs/lib/internal/Magento/Framework/Data/Argument/Interpreter/Composite.php(61): Magento\Framework\App\Arguments\ArgumentInterpreter->evaluate(Array) #2 /var/www/web22/htdocs/lib/internal/Magento/Framework/ObjectManager/Config/Mapper/Dom.php(102): Magento\Framework\Data\Argument\Interpreter\Composite->evaluate(Array) #3 /var/www/web22/htdocs/lib/internal/Magento/Framework/Config/Reader/Filesystem.php(176): Magento\Framework\ObjectManager\Config\Mapper\Dom->convert(Object(DOMDocument)) #4 /var/www/web22/htdocs/lib/internal/Magento/Framework/Config/Reader/Filesystem.php(132): Magento\Framework\Config\Reader\Filesystem->_readFiles(Object(Magento\Framework\C in /var/www/web22/htdocs/lib/internal/Magento/Framework/App/ObjectManagerFactory.php on line 281