Session_start(): Failed to decode session object

Need Help
1

I use a DevContainer for developing my component with CakePHP 4. Quite normal: Docker with PHP 8.2 and MariaDB as the database. When I now call up my application, I get the following error:

Error Message:

Warning (2) : session_start(): Failed to decode session object. Session has been destroyed [in /workspaces/app/vendor/cakephp/cakephp/src/Http/Session.php, line 362]
Warning (512) : Unable to emit headers. Headers sent in file=/workspaces/app/vendor/cakephp/cakephp/src/Error/Renderer/HtmlErrorRenderer.php line=37 [in /workspaces/app/vendor/cakephp/cakephp/src/Http/ResponseEmitter.php, line 71]
Warning (2) : Cannot modify header information - headers already sent by (output started at /workspaces/app/vendor/cakephp/cakephp/src/Error/Renderer/HtmlErrorRenderer.php:37) [in /workspaces/app/vendor/cakephp/cakephp/src/Http/ResponseEmitter.php, line 164]
Warning (2) : Cannot modify header information - headers already sent by (output started at /workspaces/app/vendor/cakephp/cakephp/src/Error/Renderer/HtmlErrorRenderer.php:37) [in /workspaces/app/vendor/cakephp/cakephp/src/Http/ResponseEmitter.php, line 197]

Can someone give me a tip or a hint about what this error message is trying to tell me? I have checked everything and found nothing unusual.

My app settings are as follows:

'Session' => array(
    'defaults' => 'database',
    'timeout'  => 15,
),
2

Hey there,
I guess the error message indicates a problem decoding session data, likely due to a serialization issue. Check for any output before session_start(), review your database connection, and ensure the session table exists and is configured correctly. If the problem persists, consider debugging CakePHP’s session handling or seeking help from the CakePHP community.

3

Thank you very much. I actually debugged everything completely and then was able to determine that the entries in the database were being deleted. After that, I discovered that the Devcontainer had the wrong time, causing all sessions to expire immediately. After updating the Devcontainer, everything is working again.