Fatal error: Uncaught Symfony\Component\Debug\Exception\UndefinedFunctionException: Attempted to call function "simplexml_load_string" from namespace "Doctrine\ORM\Mapping\Driver". in /home/tafsiror/public_html/WEB_ROOT/main/vendor/doctrine/orm/lib/Doctrine/ORM/Mapping/Driver/XmlDriver.php:848 Stack trace: #0 /home/tafsiror/public_html/WEB_ROOT/main/vendor/doctrine/persistence/lib/Doctrine/Persistence/Mapping/Driver/FileDriver.php(93): Doctrine\ORM\Mapping\Driver\XmlDriver->loadMappingFile('/home/tafsiror/...') #1 /home/tafsiror/public_html/WEB_ROOT/main/vendor/doctrine/orm/lib/Doctrine/ORM/Mapping/Driver/XmlDriver.php(60): Doctrine\Persistence\Mapping\Driver\FileDriver->getElement('FOS\\UserBundle\\...') #2 /home/tafsiror/public_html/WEB_ROOT/main/vendor/doctrine/persistence/lib/Doctrine/Persistence/Mapping/Driver/MappingDriverChain.php(79): Doctrine\ORM\Mapping\Driver\XmlDriver->loadMetadataForClass('FOS\\UserBundle\\...', Object(Doctrine\ORM\Mapping\ClassMetadata)) #3 /home/tafsiror/public_html/WEB_ROOT/main/vendor/doc in /home/tafsiror/public_html/WEB_ROOT/main/vendor/doctrine/orm/lib/Doctrine/ORM/Mapping/Driver/XmlDriver.php on line 848