Модератору - Ваш почтовый сервер не работает

Послал Вам письмо о том, что не получаю уведомлений о новых фотографиях авторов. Но email вернулся. Вот Вам подробности:
his is the Postfix program at host club.foto.ru.

I'm sorry to have to inform you that your message could not be be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can delete your own text from the attached returned message.

The Postfix program

<moderator@club.foto.ru>: unknown user: "moderator"