Furthermore, you can enable the HSTS setting to improve security.
1. The .htaccess is not writable, or not available.
2. Testing of the .htaccess rewrite rules failed. This can be caused by several things:
- The plugin couldn’t access the test page: some configurations do not allow access to the plugin from a URL.
- Your server does not pass a server variable that indicates the SSL protocol. This is needed if you want to redirect all requests in .htaccess.