Sending email via Amazon SES SMTP error

Question

I'm trying to send email via Amazon SES new SMTP service using .NET's built-in SmtpClient

Code:

    var emailClient = new SmtpClient("email-smtp.us-east-1.amazonaws.com", 465);
                    emailClient.EnableSsl = true;
....
emailClient.Send(message);

I get an exception:

Unable to read data from the transport connection: net_io_connectionclosed

Google says this error means that I can't reach SMTP server. They require TLS which I beleive achieved by "EnableSsl" property.

Anybody know how I need to tweak my code to make it work?

EDIT:

I guess I will close this question. No, it's not possible to do what I want with SmtpClient

https://forums.aws.amazon.com/thread.jspa?messageID=302112&#302112

Answer 1

It is possible to do this by specifying port 587.

<system.net>
   <mailSettings>
     <smtp deliveryMethod="Network">
       <network enableSsl="true" port="587" host="email-smtp.us-east-1.amazonaws.com" password="[password]" userName="[username]"/>
     </smtp>
   </mailSettings>
</system.net>

With that as the configuration, you can use the SmtpClient as you normally would

var client = new SmtpClient();
var message = new MailMessage(fromemail, recipient, subject, body);
client.Send(message);

Answer 2

I can confirm that it works with STARTTLS and port 587.

Hope that helps

Answer 3

According to Amazon - it is not supported as we used to.

https://forums.aws.amazon.com/thread.jspa?messageID=302112&#302112

The .NET email TLS libraries only support STARTTLS which SES does not support today. We support what is called "TLS Wrapper" or SMTPS authentication. I can understand how this would be frustrating, but you can use OpenSSL as a workaround and tunnel through that software running on your computer to use .NET to program against our SMTP endpoint.

Answer 4

As masterfu mentions in his blog post, Amazon SES started supporting STARTTLS in March of 2012.

Below is the code that I used to get SMTP working with Amazon.

  string username = ConfigurationManager.AppSettings["AWSSMTPUser"];
  string password = ConfigurationManager.AppSettings["AWSSMTPPass"];

  SmtpClient smtp = new SmtpClient();
  smtp.Host = "email-smtp.us-east-1.amazonaws.com";
  smtp.Port = 587;
  smtp.UseDefaultCredentials = false;
  smtp.Credentials = new NetworkCredential(username, password);
  smtp.EnableSsl = true;

  smtp.Send(mail);

Answer 5

Now SES supports STARTTTLS:

Outgoing server (SMTP)—25, 587, or 2587 (to connect using STARTTLS), or 465 or 2465 (to connect using TLS Wrapper).

Pruf link: http://s3.amazonaws.com/awsdocs/ses/latest/ses-dg.pdf

Answer 6

For Anyone who wants to send with normal .Net SMTPClient. It is possible as you just need a wrapper.

Here's a link with all the info:

http://docs.amazonwebservices.com/ses/latest/DeveloperGuide/SMTP.Client.html

Install the tunneling software and configure as the describe in the link then its as simple as :

System.Net.Mail.SmtpClient sc = new SmtpClient();
sc.Host = host;
sc.Port = port;
sc.Credentials = new NetworkCredential(username, password);
sc.Send(mm);

Answer 7

Try using port no. 2587, other port 25, 425, 587 dint work for my case.

Answer 8

你在web.config中设置了defaultCredentials =“false”吗？