mysqli::rollback(): MySQL server has gone away

Mình cài Xenforo thì bị lỗi này:

1. XenForo_Application::handlePhpError()
2. mysqli->rollback() in Zend/Db/Adapter/Mysqli.php at line 444
3. Zend_Db_Adapter_Mysqli->_rollBack() in Zend/Db/Adapter/Abstract.php at line 523
4. Zend_Db_Adapter_Abstract->rollBack() in XenForo/Db.php at line 112
5. XenForo_Db::rollback() in XenForo/Db.php at line 136
6. XenForo_Db::rollbackAll() in XenForo/Model/Deferred.php at line 265
7. XenForo_Model_Deferred->runDeferred() in XenForo/Model/Deferred.php at line 390
8. XenForo_Model_Deferred->_runInternal() in XenForo/Model/Deferred.php at line 316
9. XenForo_Model_Deferred->runByUniqueKey() in XenForo/Install/Controller/Abstract.php at line 34
10. XenForo_Install_Controller_Abstract->_manualDeferredRunner() in XenForo/Install/Controller/Install.php at line 236
11. XenForo_Install_Controller_Install->actionRunDeferred() in XenForo/FrontController.php at line 347
12. XenForo_FrontController->dispatch() in XenForo/FrontController.php at line 134
13. XenForo_FrontController->run() in /home/vol1_2/freevnn.com/freev_14729143/htdocs/install/index.php at line 18

Trước đó đã cài được nhưng bị thiếu files nên unload lại, không biết có sao không?