The AllowOverride tag in the apache config file for your website is probably set to “None”, it needs to be set to “All”. This would prevent the .htaccess file in the User Guide from taking effect.
Here is mine for a reference, you’d have to check with your host to see if you have access to change it. The apache web server would have to be restarted for the changes to take effect I think.
<VirtualHost *:80>
DocumentRoot /var/www
<Directory />
Options FollowSymLinks
AllowOverride All
</Directory>
<Directory /var/www>
Options Indexes FollowSymLinks MultiViews
AllowOverride All
Order allow,deny
allow from all
</Directory>
... rest removed for space ...
</VirtualHost>