A PHP Error was encountered Severity: Warning Message: mkdir(): Invalid path Filename: drivers/Session_files_driver.php

The error message mkdir(): Invalid path in Session_files_driver.php typically occurs in a CodeIgniter application when the framework is unable to create the session files directory. This issue could be due to an invalid or misconfigured session save path. Here’s how you can troubleshoot and fix this issue:

Steps to Fix the Error:

1. Check Session Save Path Configuration:
   • Open your application/config/config.php file.
   • Look for the following configuration line:
     php

     $config['sess_save_path'] = NULL;

   • Ensure that the session save path is correctly set. If it’s NULL, CodeIgniter will attempt to use the default system temporary directory. You can set a custom path like this:
     php

     $config['sess_save_path'] = '/path/to/your/session/directory'; (You can also use php function “sys_get_temp_dir();” as the path for it)
   • Make sure that the directory you specify exists and is writable by the web server.
2. Check Directory Permissions:
   • If you’ve set a custom path for session files, ensure that the directory exists and has the appropriate permissions.
   • The web server user (e.g., www-data, apache, nginx, etc.) must have write permissions to this directory. You can set the permissions using: bash
     chmod 0777 /path/to/your/session/directory

   • Alternatively, you can adjust the permissions to a more secure setting that allows only the web server to write to the directory:
     bash

     chmod 0700 /path/to/your/session/directory

3. Verify the Path Validity:
   • Ensure that the path you provided does not contain any typos or invalid characters.
   • Make sure the path is absolute (e.g., /var/www/html/sessions) rather than relative.
4. Check PHP Configuration:
   • If you’re using the default system temporary directory, make sure that the sys_temp_dir setting in your php.ini file is correctly set and writable.
   • You can find this setting by searching for sys_temp_dir in the php.ini file.
5. Restart the Web Server:
   • After making the changes, restart your web server to ensure the new configuration is applied:
     bash

     sudo service apache2 restart # For Apache
sudo service nginx restart # For Nginx

6. Check for CodeIgniter Version Compatibility:
   • Ensure that you are using a compatible version of CodeIgniter with your PHP version. In some cases, an outdated or incompatible CodeIgniter version can cause issues with session handling.

By following these steps, you should be able to resolve the mkdir(): Invalid path error and ensure that your sessions are being stored correctly.