500 Error Class 'sfLoader' not found

Hello,

I am getting these errors in the log:
PHP Fatal error: Class ‘sfLoader’ not found in /opt/kaltura/app/vendor/symfony/config/sfConfigCache.class.php on line 157

This causes error 500 in Kaltura.

Any ideas

What are you trying to do when you get the 500?
What does rpm -qa | grep kaltura-server* give you?

I try to login to a publisher UI.

kaltura-server-15.11.0-1.noarch

Could you please run kaltlog on the server while trying to login and share additional error messages related to the issue.

There were no additional error messages.

I already used a backup of the server from two days ago and it works ok now.

Still have no idea which service was wrong.

Thanks for helping with this question!