403 when opening "/mw-config/index.php" for configuring MediaWiki on WAMP

I'm following this guide: https://www.mediawiki.org/wiki/Manual:Ruing_MediaWiki_on_Windows#Installing_MediaWiki

When I try to open "http://domain/directory/mw-config/index.php" with domain=localhost and directory=C:/wamp/www/wiki I get:

Forbidden

You don't have permission to access /C:/wamp/www/wiki/mw-config/index.php on this server. Apache/2.4.18 (Win32) PHP/5.6.19 Server at localhost Port 80

How to solve this?