I have hosted web application develop using joomla in ubuntu 20 and use mysql as database. one i hosted and viewed in the web browser it show me Error: Failed to start application: Failed to start the session

i have used php 7.4, mysql Ver 8.0.27, apache Apache/2.4.41 (Ubuntu)

  • Please take our tour while you wait for feedback/support. We are likely to need more details. Is this a new build? If not, what has recently changed? You may edit your question whenever and as often as you like. Is this question different from your previous question? Commented Feb 1, 2022 at 10:28

2 Answers 2


Joomla works with sessions. It needs to be able to write session info to the #__session table in the database. Your error message indicates that Joomla cannot write to the database, hence it cannot start its session.

Could you double check your MySQL credentials with the credentials in your configuration.php?

 public $dbtype = 'mysqli';
 public $host = 'localhost';
 public $user = 'some-user';
 public $password = 'some-secret-password';
 public $db = 'the-name-of-your-database';
 public $dbprefix = 'the-table-prefix_';
  • I have check by using mysql -u {name} -p command by using the values in the configuration.php file and it work and log into mysql database.
    – udakila
    Commented Feb 2, 2022 at 4:43
  • Ok, something else to check: can PHP access your MySQL database. Do you have the PHP module php-mysql installed on the server? Could you use the forumpostassistant.github.io/docs to analyze your website / server environment?
    – pe7er
    Commented Feb 2, 2022 at 8:50
  1. Common causes for the “failed to start session” error in Joomla: see https://forum.joomla.org/viewtopic.php?t=982009

  2. Make sure that your version of PHP can connect to the database: see Optional Technical Requirements for J! 3.x

  1. Unusual causes for this error: (a) Tinkering with the file configuration.php to change the SQL user password; or (b) Is your disk full?

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.