Question

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

Answer 1

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