Hi Roland.

In general it's Joomla issue, sometimes that area goes "crazy". Sorry this time forum.joomla.org - releated topics.

About 2nd:

1. Please reinstall SPPB component
2. Clear Joomla cache || J! Admin > System > Maintenance > Clear Cache > Select the Delete All and then Clear Expired Cache buttons in the toolbar.
3. Clear browser cache
4. Check SPPB again

It helps in 99% cases ;)

Do I have to uninstall PageBuilder first? If yes how?

No, just reinstall. Install again that same version as you have! I guess Pro.

File is here: https://www.joomshaper.com/downloads/extension

I did everything exactly the same, unfortunately still the same error!

Hmm.

1. Have you tested site using two different browsers?
2. What Joomla and PHP version?
3. Share access to admin area (Super User).

1. Yes
2. 8.2
3. done

Danke.

In Hosting cPanel please change:

1. PHP Memory Limit from unlimited (-1) to 256M or 512M
2. Disable Mod_Security for today

if you don't know how - ask hosting support to help.

Then AFTER - check SPPB again.

But the main problem is with:

Eine Anfrage an eine Ressource eines anderen Ursprungs wurde blockiert: die Same Origin Policy erlaubt es nicht, entfernte Ressourcen von "administrator/index.php?option=com_sppagebuilder&task=/editor.addons&type=&_method=get" zu laden (fehlender CORS-Header "Access-Control-Allow-Origin"). Status-Code: 301.

That's why also Notifications from Joomla Admin does not work!

Please ask Hosting Support how you can disable/change that. Maybe its from mod_security settings.

OK, first of all, thank you very much. I'll talk to IONOS and hope that the error can then be resolved.

I done what I could. Whole rest now is in support hands.

You're welcome

Hello Paul, the PHP limit has been increased. But IONOS doesn't know how to change the mod_security settings. Unfortunately, after the PHP limit was increased, the error still occurs. Do you know how I can change the mod_security settings?