I'm using Version 5.2.4 of Mail on Update and WordPress 3.8.1 is giving me the following error:
admin-functions.php is <strong>deprecated</strong> since version 2.5!
I believe from
I can post a stack trace/other info if you need.
Easily fixed by editing line 124 to:
@require_once ( ABSPATH . 'wp-admin/includes/admin.php');