Leftover - akeeba/onthos GitHub Wiki

This is an extension which appears in the #__extensions database table, but its main executable files / directories are no longer present on your site.

Because critical files / directories are missing, Joomla! cannot uninstall this extension, therefore it cannot remove the database record.

Why is it a problem?

This is a non-functional extension. It's missing the code files which would make it work.

If it no longer receives updates, you will see this extension appearing as incompatible –potentially misleading you away from upgrading your site– when you try to update Joomla. Other extensions which depend on or interoperate with this extension will have no way to tell that this extension is not really installed and might end up breaking due to the unexpected discrepancy of what Joomla! says is installed, and what is actually installed. Finally, if none of the above is a problem, just the fact that you have a leftover record confusing you in the list of extensions is reason enough for most people to address this issue – that was the impetus to making Onthos in the first place.

Suggested fix

Uninstall the errant record.

You can only do so using Onthos' Forced Uninstall feature. Joomla! will be unable to remove the extension record by itself.