overnoise

I think that the problem is this: http://core.trac.ww.wp.xz.cn/ticket/17090#comment:19

it worked for me.

We had modifed the following code from the file “admin.php” in the path “/wp-admin/network”.

=========== Previous Code

if ( ( $current_blog->domain != $current_site->domain ) || ( $current_blog->path != $current_site->path ) ) {
wp_redirect( network_admin_url() );
exit;
=========== Corrected Code

if ( ! is_main_site() ) {
wp_redirect( network_admin_url() );
exit;