I installed the Joomla system by uploading it in the online file manager, where I extracting.
The installation went fine and the site went up, perfect!
But every extension I try to install fails the error above.
I have tried all kinds of solutions within Joomla, but there seems to be no connection to CMS but to server.
I deleted the files and re-extracting, and reinstalled, the problem remained.
I completely deleted the database and created a new one.
I uploaded a new Joomla file from an older version, the problem remained the same!
During all these steps, I also tried to change folder permissions, at least temporarily for it to work, but there is no difference.
I can’t figure out what the problem is, I suspect there may be a problem with proper file ownership.
In addition, I have tried the “Troubleshoot and Fix Your Website” in the admin panel, again, no difference.
Thank you very much for your help!