It's not because of the template, it works.
You have to give more information.
what operating system are you using locally?
What settings did you use during installation?
Which access data do you use (DO NOT write any PASSWORDS!)
Which host?
Do you have all permissions to create a database?
Are your server checks correct before you click install?


Some screenshots would also be good?

Hi eumel7,

Local I use Mamp, latest version, on Mac with OS 10.15.
But more importent is the installation online. At a good provider, where I already installed dozens of Joomlasites with the help of Akeeba backup without any problem. Now I use the same settings as always.

'Settings during installation'? I had not yet any opportunity to do any setting. I just made a subdomain, as I made it a lot of times for Joomla-sites. PHP = 7.4. Don't use passwords. Host is localhost. And yes, a database is ready - but the process stopped before I could use the database.
What server checks do you mean?
Screenshot from what?

And yes, the template is okay. But the installation package, the 'Demo-installer' seem to be corrupt. And in this case I need more than only the template.

Hello tralala.
Thank you for your further information. Unfortunately it was not clear from your first posting that you have experience installing Joomla. In general, there is often too little information about the problem here in the forum. This led me to believe that you are a beginner. That's not the case.
Unfortunately I don't have the Nina template and I can't understand your error.

Thank you

I have updated and rebuilt the template demo installer to the latest version of Joomla (4.1.2) which I am hoping will resolve this issue. The updated demo installer is now available via your template downloads bundled with the Nina template.

Ciaran

Thanks!
This works - a litte bit.
The installation starts. But after entering database configuration I got this warning: "Duplicate entry '700-4.1.1-2022-02-20' for key 'PRIMARY' "

I don't know what this means. I tried once and again, the warning changed in the hated "Could not connect to database: Access denied for user..".

My problem, I'm afraid. But: the Demo-installations seems to work.

This Demo-installer seems still to be fucked up.
I tried is once and again and again and again local, so I can controll everything.

1. During installation, after database configuration, hitting 'Install Joomla' I get the warning:
Duplicate entry '700-4.1.1-2022-02-20' for key 'PRIMARY'
2. Just hitting again 'Install Joomla' gives (in dutch) "Het beveiligingstoken komt niet overeen. Het verzoek werd afgebroken om een inbreuk op de beveiliging te voorkomen. Probeer nogmaals." In English: "The safety token doesn't match. The request was aborted to prevent a security breach. Try again."
3. Just trying again gives again the warning Duplicate entry '700-4.1.1-2022-02-20' for key 'PRIMARY'. And so on.
This happens with of without choosing SSL.

4. Surprise: refreshing the browser window results in "Congratulations, your Joomla site is ready".

Opening Admin fails.
Opening the site succeeds. But logging in fails. "Not Found. The requested URL was not found on this server'"

Are you interested in the configuration.php ?

Hello

Could I ask you to test the latest download. We have tested the latest and all appears to install without issue on multiple env.

Thank you for your patience!

Ciaran