Mailbox unavailable when sending to an external address

[SCantoria]

I have to email sender class. 1 for the sending to external addresses using namespace System.Web.Mail and another for sending to internal address using namespace System.Net.Mail.

I would like to only use System.Net.Mail for both internal and external emials. The problem I ran into is "Mailbox Unavailable" when sending to external email addresses.

public EmailSender(string From, string To, string Bcc, string Subject, string Body)
{
this.m_strFrom = From;
this.m_strTo = To;
this.m_strBcc = Bcc;
this.m_strSubject = Subject;
this.m_strBody = Body;
this.m_strAttachment = Attachment;

/// instantiate MailMessage class
///
MailMessage mail = new MailMessage();

/// set addresses
///
mail.From = new MailAddress(m_strFrom);
mail.To.Add(m_strTo);
mail.Bcc.Add(m_strBcc);

/// set mail content
///
mail.Subject = m_strSubject;
mail.Body = m_strBody;

/// set mail body type to HTML
///
AlternateView htmlmail = AlternateView.CreateAlternateViewFromString(m_strBody, null, "text/html");
mail.AlternateViews.Add(htmlmail);

/// send mail to defined smtp server
///
SmtpClient smtp = new SmtpClient("heops-s01.heops.local");
smtp.Send(mail);
}

 

[ca8msm]

If you are getting a failure sending to external email addresses, but can send to internal ones, it's more likely to be an issue with your SMTP server rather than an ASP.NET one.

Mark,

Darlington Web Design
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