We do not relay non-local mail,Mailbox name not allowed. What does it mean

1
votes

I am trying to send email via System.Net.Mail. On clicking send I am getting the following exception

System.Net.Mail.SmtpFailedRecipientException: Mailbox name not allowed. The server response was: We do not relay non-local mail

        MailAddress toAddress = new MailAddress(toEmail);
        MailAddress fromAddress = new MailAddress(fromEmail);
        MailMessage mailMsg = new MailMessage(fromAddress, toAddress);

        mailMsg.Subject = EmailSubject;
        mailMsg.Body = MessageBody.ToString();
        mailMsg.IsBodyHtml = true;


        System.Net.Mail.SmtpClient smtp = new SmtpClient(EmailSettings.SmtpServer);
        smtp.Send(mailMsg);

That is all I am doing.

What workaround should I take for this to work

2
asp.netemailsmtp
use a local smtp server (in your domain) or find one that does allow relaying with authentication. – Mitch Wheat
It'll help if you show some code, and anything related that you've defined in your web.config if applicable. – Brissles
both the to and from address are from the same server – Sandhurst
@Sandhurst: That might be not enough. Not only they have to be from the same server but also that server name should equal EmailSettings.SmtpServer value - including subdomains. – Sergey Kudriavtsev

2 Answers

2
votes

You should authenticate your SMTP client using credentials AND sender mailbox belonging to SMTP server you're connecting to.

0
votes

Also (depending on your mail server) the fromAddress needs to be an actual account on the mail server.