My WordPress installation doesn’t load correct template

I found a solution.

Installing the plugin, as mentioned above, Rewrite Rules Inspector indicated nothing wrong at all.

However, installing the plugin No Category Base (WPML) and simply activated it, was enough to resolve the issue in every instance of it returning an error.

I am afraid this might indicate something very wrong with my installation, but either way I’m up’n’running now.

Thanks for inputs!