diff --git a/wp-includes/ms-files.php b/wp-includes/ms-files.php
index f41639dd5..f5af8e037 100644
--- a/wp-includes/ms-files.php
+++ b/wp-includes/ms-files.php
@@ -11,6 +11,9 @@
 define( 'SHORTINIT', true );
 require_once( dirname( dirname( __FILE__ ) ) . '/wp-load.php' );
 
+if( !is_multisite() )
+	die( 'Multisite support not enabled' );
+
 ms_file_constants();
 
 error_reporting( 0 );
@@ -77,4 +80,4 @@ if ( ( $client_last_modified && $client_etag )
 
 // If we made it this far, just serve the file
 readfile( $file );
-?>
\ No newline at end of file
+?>