Failed Ajax request or invalid JSON returned ojs3.3.0.13

Software Support
1

i used ojs3.3.0.13 and it was working fine, but suddenly it stopped working and this message appears (Failed Ajax request or invalid JSON returned) and I cannot do any operation to add, modify or upgrade add-ons and the added requests do not appear and these are some of the errors that appear in the file (error_log)

[24-Nov-2022 21:43:16 UTC] PHP Fatal error:  Uncaught PDOException: SQLSTATE[28000] [1045] Access denied for user 'ojs'@'localhost' (using password: YES) in /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php:38
Stack trace:
#0 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php(38): PDO->__construct()
#1 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(67): Doctrine\DBAL\Driver\PDOConnection->__construct()
#2 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(46): Illuminate\Database\Connectors\Connector->createPdoConnection()
#3 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\Database\Connectors\Connector->createConnection()
#4 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(184): Illuminate\Database\Connectors\MySqlConnector->connect()
#5 [internal function]: Illuminate\Database\Connectors\ConnectionFactory->Illuminate\Database\Connectors\{closure}()
#6 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(926): call_user_func()
#7 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(961): Illuminate\Database\Connection->getPdo()
#8 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(405): Illuminate\Database\Connection->getReadPdo()
#9 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(360): Illuminate\Database\Connection->getPdoForSelect()
#10 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(664): Illuminate\Database\Connection->Illuminate\Database\{closure}()
#11 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(631): Illuminate\Database\Connection->runQueryCallback()
#12 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(373): Illuminate\Database\Connection->run()
#13 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(112): Illuminate\Database\Connection->cursor()
#14 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(88): PluginSettingsDAO->getPluginSettings()
#15 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/cache/GenericCache.inc.php(63): PluginSettingsDAO->_cacheMiss()
#16 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(59): GenericCache->get()
#17 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/Plugin.inc.php(463): PluginSettingsDAO->getSetting()
#18 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/LazyLoadPlugin.inc.php(68): Plugin->getSetting()
#19 /home/fezzanuedu/public_html/FUSJ/plugins/generic/staticPages/StaticPagesPlugin.inc.php(50): LazyLoadPlugin->getEnabled()
#20 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(69): StaticPagesPlugin->register()
#21 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(142): PluginRegistry::register()
#22 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(211): PluginRegistry::loadCategory()
#23 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/install/Installer.inc.php(98): PluginRegistry::loadAllPlugins()
#24 /home/fezzanuedu/public_html/FUSJ/classes/install/Upgrade.inc.php(27): Installer->__construct()
#25 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/install/form/UpgradeForm.inc.php(37): Upgrade->__construct()
#26 /home/fezzanuedu/public_html/FUSJ/lib/pkp/pages/install/InstallHandler.inc.php(130): UpgradeForm->execute()
#27 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPRouter.inc.php(395): InstallHandler->installUpgrade()
#28 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPPageRouter.inc.php(246): PKPRouter->_authorizeInitializeAndCallRequest()
#29 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/Dispatcher.inc.php(144): PKPPageRouter->route()
#30 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPApplication.inc.php(362): Dispatcher->dispatch()
#31 /home/fezzanuedu/public_html/FUSJ/index.php(68): PKPApplication->execute()
#32 {main}

Next Doctrine\DBAL\Driver\PDO\Exception: SQLSTATE[28000] [1045] Access denied for user 'ojs'@'localhost' (using password: YES) in /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDO/Exception.php:18
Stack trace:
#0 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php(42): Doctrine\DBAL\Driver\PDO\Exception::new()
#1 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(67): Doctrine\DBAL\Driver\PDOConnection->__construct()
#2 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(46): Illuminate\Database\Connectors\Connector->createPdoConnection()
#3 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\Database\Connectors\Connector->createConnection()
#4 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(184): Illuminate\Database\Connectors\MySqlConnector->connect()
#5 [internal function]: Illuminate\Database\Connectors\ConnectionFactory->Illuminate\Database\Connectors\{closure}()
#6 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(926): call_user_func()
#7 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(961): Illuminate\Database\Connection->getPdo()
#8 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(405): Illuminate\Database\Connection->getReadPdo()
#9 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(360): Illuminate\Database\Connection->getPdoForSelect()
#10 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(664): Illuminate\Database\Connection->Illuminate\Database\{closure}()
#11 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(631): Illuminate\Database\Connection->runQueryCallback()
#12 /home/fezzanuedu/public_html/FUSJ/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(373): Illuminate\Database\Connection->run()
#13 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(112): Illuminate\Database\Connection->cursor()
#14 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(88): PluginSettingsDAO->getPluginSettings()
#15 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/cache/GenericCache.inc.php(63): PluginSettingsDAO->_cacheMiss()
#16 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginSettingsDAO.inc.php(59): GenericCache->get()
#17 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/Plugin.inc.php(463): PluginSettingsDAO->getSetting()
#18 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/LazyLoadPlugin.inc.php(68): Plugin->getSetting()
#19 /home/fezzanuedu/public_html/FUSJ/plugins/generic/staticPages/StaticPagesPlugin.inc.php(50): LazyLoadPlugin->getEnabled()
#20 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(69): StaticPagesPlugin->register()
#21 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(142): PluginRegistry::register()
#22 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/plugins/PluginRegistry.inc.php(211): PluginRegistry::loadCategory()
#23 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/install/Installer.inc.php(98): PluginRegistry::loadAllPlugins()
#24 /home/fezzanuedu/public_html/FUSJ/classes/install/Upgrade.inc.php(27): Installer->__construct()
#25 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/install/form/UpgradeForm.inc.php(37): Upgrade->__construct()
#26 /home/fezzanuedu/public_html/FUSJ/lib/pkp/pages/install/InstallHandler.inc.php(130): UpgradeForm->execute()
#27 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPRouter.inc.php(395): InstallHandler->installUpgrade()
#28 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPPageRouter.inc.php(246): PKPRouter->_authorizeInitializeAndCallRequest()
#29 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/Dispatcher.inc.php(144): PKPPageRouter->route()
#30 /home/fezzanuedu/public_html/FUSJ/lib/pkp/classes/core/PKPApplication.inc.php(362): Dispatcher->dispatch()
#31 /home/fezzanuedu/public_html/FUSJ/index.php(68): PKPApplication->execute()
#32 {main}
2

no answer form anybody ,
I’ve tried all the solutions on the forum and it didn’t work And I downloaded ojs as another new site and the error-log file did not show any error, but there was the same problem, knowing that I can only modify personal data, as well as display practical papers only

3

According to the above log, I see that the MySQL database connection was not able to verify the credentials provided. Check the privilege of your MySQL database connection, credentials.

4

This message indicates that there is no access to the database.
First you have to validate in your DB the username and password that you defined in your config.ini.php are the same.