WordPress Default From Address (Paste into functions.php)

WP_default_from_address.php

add_filter('wp_mail_from', 'new_mail_from');
add_filter('wp_mail_from_name', 'new_mail_from_name');

function new_mail_from($old) {
 return 'admin@yourdomain.com';
}
function new_mail_from_name($old) {
 return 'Your Blog Name';
}