Hello Rutgers,
what version of PHP are you using?
I think things are getting mixed up there.
Bypassing the SQL error alone is definitely not enough here.
The installation gets wrong version information and behaves accordingly wrong.
It may have been incompletely uninstalled or there was an outdated subscription on Joomla 3.
There are definitely 2 different problems
- the images that can be copied and
- the plugin 'Mailattachments'.
If files or directories cause problems for the Joomla installer, this usually points to the server or the file system.
The most direct and therefore also the simplest would be the following:
We would like to find out what is going wrong on your Joomla instance and visforms.
To do this, we need to debug the Visforms code.
The question is whether you could provide us with an Akeeba backup of the website.
We use the following platform for this:
wetransfer.com/
Kind regards, Ingmar