This is the Postfix program at host mailgate.ufa-rb.ru. I'm sorry to have to inform you that your message could not 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 <[email protected]>: host 193.233.144.7[193.233.144.7] said: 550 [email protected] unknown user account (in reply to RCPT TO command)