The function that deals with this is
If existent, it will use the following files. And they should render a full custom HTML page.
WP_CONTENT_DIR . '/blog-deleted.php'
WP_CONTENT_DIR . '/blog-inactive.php'
WP_CONTENT_DIR . '/blog-suspended.php'
Another option is to short-circuit the process and redirect the visitor. It has to be done with a Must Use plugin and here using a PHP 5.3 anonymous function as callback.
* Plugin Name: Prevent Archived/Deleted blogs warning in Multisite
* Plugin Url: https://wordpress.stackexchange.com/q/98151/1261
* Version: 1.0
* Author: Rodolfo Buaiz
* Author URI: https://wordpress.stackexchange.com/users/12615/brasofilo
// Super admins should be able to see it
if( current_user_can( 'manage_network' ) )
$blog = get_blog_details();
'1' == $blog->deleted
or '2' == $blog->deleted
or '1' == $blog->archived
or '1' == $blog->spam
wp_redirect( network_site_url() );
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