We'll create fresh WordPress site with Disable Author Archives installed. You have 20 minutes to test the plugin after that site we'll be deleted.
A simple, lightweight WordPress plugin to completely disable author archives/pages (regardless of whether the corresponding author really exists) and make the web server return status code 404 (‘Not Found’) instead. Related links will also be either disabled or completely removed.
The plugin does not require any configuration. Once activated, it will start doing its job.