diff --git a/wp-admin/includes/update-core.php b/wp-admin/includes/update-core.php
index 34bf58212b..a7c27fdf84 100644
--- a/wp-admin/includes/update-core.php
+++ b/wp-admin/includes/update-core.php
@@ -172,6 +172,23 @@ $_old_files = array(
 'wp.php',
 'wp-includes/gettext.php',
 'wp-includes/streams.php',
+// MU
+'wp-admin/wpmu-admin.php',
+'wp-admin/wpmu-blogs.php',
+'wp-admin/wpmu-edit.php',
+'wp-admin/wpmu-options.php',
+'wp-admin/wpmu-themes.php',
+'wp-admin/wpmu-upgrade-site.php',
+'wp-admin/wpmu-users.php',
+'wp-includes/wpmu-default-filters.php',
+'wp-includes/wpmu-functions.php',
+'wpmu-settings.php',
+'index-install.php',
+'wp-admin/css/mu-rtl.css',
+'wp-admin/css/mu.css',
+'wp-admin/images/site-admin.png',
+'wp-admin/includes/mu.php',
+'wp-includes/images/wordpress-mu.png',
 // 3.0
 'wp-admin/categories.php',
 'wp-admin/edit-category-form.php',