HelpNDoc generates standard static HTML pages which can be hosted on any web server. The HTML standard doesn't provide a way to restrict access to a specific page. This is something that is achieved by the web server hosting those files.
How it is done depends on the web server technology that you are using:
- For Apache, see the Access Control and Authentication and Authorization documentation pages;
- For NGINX, see the Restricting Access with HTTP Basic Authentication documentation page;
- For Microsoft IIS, see the IP Security, Security Authorization and Security Authentication documentation pages;
- For other web servers, we recommend that you check the web server's documentation or ask for assistance to an IT professional or community forum.