Error when trying to reach multisite website.

Hello,

Today I tried installing a multisite wordpress environment becuase I need a wordpress website with two themes (one on a subdomain: intranet.domain.com, one on a normal domain). Everything went well, but when I tried to access the dashboard of my ‘new’ subdomain-website I get an error: Not Found The requested URL / was not found on this server. I did everything using the WordPress documentation. This is what the edited part of my .htaccess looks like:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^wp-admin$ wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^(wp-(content|admin|includes).*) $1 [L]
RewriteRule ^(.*\.php)$ $1 [L]
RewriteRule . index.php [L]
</IfModule>

And this is what the edited part of my wp-config file looks like:

/* Multisite */
define( 'WP_ALLOW_MULTISITE', true );
define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', true);
define('DOMAIN_CURRENT_SITE', 'koorhappyvoices.nl');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

I am currently working on a webserver without a domain attached to it, because I am refreshing a old website. Maybe that has something to do with it?

I hope you can help me with this problem

Thanks in advance,
Joël van Daalen