If you are getting the following error:

Error during session start; please check your PHP and/or webserver log file and configure your PHP installation properly. Also ensure that cookies are enabled in your browser.
session_start(): open(SESSION_FILE, O_RDWR)) failed: Permission denied (13)

You will need to perform the following steps:

1. First ensure your session.save_path in your php.ini is set correctly.
2. Check the session directory permission:
   
   1	sudo chmod 777 /var/lib/php/session/

3. If you make any change in php.ini, restart httpd
4. Clear everything (cache, cookies…) at browser.
5. Refresh and check.