Multisite (sub)Domain Mapping White Screen of Death

Hi WP,

I’ve come hoping someone here can help. I’ve been a hobbyist WP site builder for a while, and even installed a running multisite before. This has me stumped.

I’m currently helping my friend build a network of sites. She’s on a shared hosting package, and the main site for her multisite is NOT the primary site in Cpanel. I created the network, and everything’s gone fine–until the domain mapping.

Once we map the domains, the result is a big, empty white screen. I’ve tried EVERYTHING I know to do, and attempted some fixes found here as well. Nothing’s worked. Any suggestions? I’d be so grateful.

Details:
– Shared hosting via Stablehost
5 sites total on the *hosting* account (Primary, Multisite Main (2 subdomains), 3rd “top level” site
Primary site is NOT the one being used for multisite build
All domain nameservers are correctly pointing to the host

– Wildcard subdomains are active
– Sunrise.php is in the wp-content folder for the Multisite main site

Fixes I’ve tried:

A name record as domain map destination (65.60.38.44)
CNAME record
Setting domain as an “addon”
Setting domain as a “parked” domain
“IfModule” rewrite command in .htaccess (with and without)
Moving the ‘define sunrise’ line in wpconfig file (above allow MU/below)
Countless other things I can’t remember off hand

Am I missing something? Please help!

Thanks!

Check out the code below. Website removed out of respect for my friend:

define('SUNRISE', 'on');

/* Multisite */
define( 'WP_ALLOW_MULTISITE', true );

define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', true);
define('DOMAIN_CURRENT_SITE', 'REAL-SITE-HERE.com');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

# BEGIN WordPress

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]

# END WordPress