Hi there!

Sorry to hear that.

Did you change your Joomla version recently too? Which version it is? The error seems related to Joomla.

Would you please check the following discussions?

https://stackoverflow.com/questions/45849884/class-jstring-not-found

https://forum.joomla.org/viewtopic.php?f=812&p=3637980

Best Regards

Hello, Thank you for the quick response. About a month ago, I installed your "helixultimate_quickstart_j4_v2.0.5". Today I just installed "SP Page Builder Pro" over the "Lite" version. Now the entire site is error with this message "Class 'JString' not found".

Joomla! 4.0.4 Stable
PHP Version 7.4.26
SP Page Builder Component   3.8.1

The link which you sent, says to check if the file > library > string exist. No, there is no such a file.

The second link says that one can try to reinstall the Joomla. Would you recommend me as well or is there some other tipps?

Thank you Ichiro Nagata

Yes, you can try the second one, but please make sure you have a full backup of your site first to avoid data loss.

Best Regards

Hello, As risk is too high for me to reinstall the Joomla4Core I searched further. As a Hungarian pointed out, this issue must occur due to the language files. My site is using Japanese, German and English language. Japanese as well as German language have "JString" problem, English not.

It means, if I delete Japanese and German language files the Helix Ultimate Site with SP Page Builder will be at least displayed. As long as these language files exist it appears only error message.

The hungarian solved the issue, but for me, it is still complicated and uncertain.

My Helix Ultimate Site with SP Page Builder Lite was working correctly. So, I prefer deleting the Pro and continue using Lite Version till the fixed language pack comes. I am afraid if the issue would remain even after deleting the Pro Version though.

Would you tell me if the following procedure is OK?

1. uninstall Pro with all SP Page Builder related files, like component, module, plugin, etc.
2. install SP Page Builder Lite

Please tell me if you ever find any "easy" solutions. I appreciate. Best Regards, Ichiro Nagata

Hi, I had the same problem after an update from Joomla 3 to 4: Class 'JString' not found. This was solved from the language used. It is important to update the language used from the administration before updating Joomla. Go to : Extentions > Language > Install Languages > Choose : English or other language used > Reinstall.

Best regards. ESF