Multisite WP produces 404 on all posts and pages

I just installed new version of WP 4.8 and set it up as multisite. I have no problems to access wp-admin on all sub-domains I set. I have no problems to create/edit posts/pages. However when I try to access post/page I’m getting 404 page.
Here is my .htaccess:
RewriteEngine On
RewriteBase /mybase/
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]

And in wp-config.php I have following:
define(‘WP_ALLOW_MULTISITE’, true);
define(‘MULTISITE’, true);
define(‘SUBDOMAIN_INSTALL’, true);
define(‘DOMAIN_CURRENT_SITE’, ‘localhost.com’);
define(PATH_CURRENT_SITE’, ‘/mybase/’);
define(‘SITE_ID_CURRENT_SITE’, 1);
define(‘BLOG_ID_CURRENT_SITE’);

Thank you for help.