WP Multisite: Redirect loop after migrating to real server

I was developing a multisite mydomain.dev locally on my machine. Everything works fine on my local machine. It was previously a normal site.

The transfer to the real server:

1.) I exported the local database.
2.) I edited the database with sublime and with search-replace replaced all “mydomain.dev” to “mydomain.com”
3.) I imported the sql file to the real database
4.) I uploaded my entire file-list.
5.) I change the wp-config.php file to the real mysql credentials on my server.
6.) I also changed the define(‘DOMAIN_CURRENT_SITE’, ‘mydomain.com’); //was mydomain.dev

/* Multisite */
define('WP_ALLOW_MULTISITE', true);
define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', false);
define('DOMAIN_CURRENT_SITE', 'oegs.dev');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

define('ADMIN_COOKIE_PATH', '/');
define('COOKIE_DOMAIN', '');
define('COOKIEPATH', '');
define('SITECOOKIEPATH', '');

7.) I also uploaded the .htaccess file to the server

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

So, to sum it up. I have edited the entire .sql Database to my real domainname. I’ve edited the config.php file to the real domainname.

On my real server the site doesn’t work. I get a redirect loop (on the homepage as well on /wp-admin).

Why? Any ideas?

Kind Regards, Sepp88