Symptoms
One of the following error messages appear in Plesk:
Error in Plesk: Zend_Controller_Exception: Session token has expired.
Zend_Controller_Exception: Permission denied.#0
PleskPermissionDeniedException: Session token has expired.
Suddenly Unexpected token < in JSON at position 0
The following message is logged in Plesk log file
/var/log/plesk/panel.log:# grep 'protection token check' /var/log/plesk/panel.log
ERR [panel] Forgery protection token check failed.
Cause
Sessions time for forgery protection token has exceeded.
Resolution
Connect to the Plesk server via RDP.
If there is a stuck process in Plesk, cancel it.
Open the file
php.inilocated in%plesk_dir%adminconf.Increase the
session.gc_maxlifetimevalue:session.gc_maxlifetime=86400
Save the changes and close the file.
Open Plesk Services Monitor and restart Plesk Management Service.