Cannot send email in ASP.NET through Godaddy servers

1- If your site is hosted on godaddy you may use "relay-hosting.secureserver.net" without credentials.

2- If your site is hosted outside of godaddy you may use "smtpout.secureserver.net" with you email account credentials.

PS: Please change port 3535 if you have problems with 25

Hosted On GoDaddy

    <system.net>
      <mailSettings>
       <smtp from="[email protected]">
        <network host="relay-hosting.secureserver.net"/>
       </smtp>
      </mailSettings>
    </system.net>

External

  <system.net>
    <mailSettings>
      <smtp from="[email protected]">
        <network host="smtpout.secureserver.net" 
           userName="[email protected]" password="your_password_here" 
           port="25" />
      </smtp>
    </mailSettings>
  </system.net>

Here's my email class:

public class Email
{
    public enum MailAddressType
    {
        From = 1,
        Bcc
    }

    private static MailAddress _from = null;

    public static void SendEmail(string to, string subject, string body)
    {
        SendEmail(to, subject, body, From, string.Empty);
    }

    public static void SendEmail(string to, string subject, string body, string from)
    {
        SendEmail(to, subject, body, from, MailAddressType.From);
    }

    public static void SendEmail(string to, string subject, string body, string addresses, MailAddressType addressType)
    {
        MailAddress from = From;
        string bcc = string.Empty;

        if (MailAddressType.From == addressType)
        {
            from = new MailAddress(addresses);
        }
        else
        {
            bcc = addresses;
        }

        SendEmail(to, subject, body, from, bcc);
    }

    private static void SendEmail(string to, string subject, string body, MailAddress from, string bcc)
    {
        MailMessage message = new MailMessage();
        message.From = From;
        message.To.Add(to);
        if (!string.IsNullOrEmpty(bcc))
        {
            message.Bcc.Add(bcc);
        }
        message.ReplyTo = from;
        message.Subject = subject;
        message.Body = HttpContext.Current.Server.HtmlEncode(body);
        SmtpClient smtp = new SmtpClient();
        smtp.Send(message);
    }

    public static MailAddress From
    {
        get
        {
            if (null == _from)
            {
                SmtpSection section = (SmtpSection)ConfigurationManager.GetSection("system.net/mailSettings/smtp");
                string address = section.From;
                string displayName = ConfigurationManager.AppSettings["fromEmailDisplayName"];
                _from = new MailAddress(address, displayName);
            }
            return _from;
        }
    }
}

And here are the related web.config settings:

<appSettings>
    <add key="fromEmailDisplayName" value="Firstname Lastname"/>
</appSettings>

<system.net>
    <mailSettings>
        <smtp deliveryMethod="Network" from="[email protected]">
            <network host="relay-hosting.secureserver.net" />
        </smtp>
    </mailSettings>
</system.net>

For me, the key was "message.From = From" and "message.ReplyTo = from". GoDaddy seems to want the message to come from an address in your domain. So for contact pages, use your default email address as the From and set the sender as the ReplyTo. Email goes through fine after that.