Sending emails that requires a secure connection

Question

REMAKING QUESTION

This code doesn't work

The error is: The remote certificate is invalid according to the validation procedure.

var client = new SmtpClient("smtp.domain.com.br", 25000)
{
    Credentials = new NetworkCredential("username", "password"),
    EnableSsl = true
};
client.Send("emailfrom@domain.com.br", "emailto@gmail.com", "test", "testbody");
// I also tested like this
// client.Send("emailfrom@domain.com.br", "emailto@domain.com", "test", "testbody");

But this code works

var client = new SmtpClient("smtp.gmail.com", 587)
{
    Credentials = new NetworkCredential("username", "password"),
    EnableSsl = true
};
client.Send("emailfrom@domain.com.br", "emailto@gmail.com", "test", "testbody");

I tested the first code data in the Outlook, and works if I try to send to an email from the same domain.

I believe that the error is some SMTP configuration, but I don't know how to solve this. Any help?

Answer 1

I solve this using the digital certificate generated in the outlook and putting it on the server, where my application is running.

With the code in my question plus the certificate I finally made this works.

Here is a link on How to do this: create your own digital certificate

Answer 2

which smtp server you using ? if you are using gmail smtp server then you must use port number 587 that is required to send through gmail

Answer 3

based on the answer below you can pass in the values from the .config file but you will have to change what I have ..test this using hard coded values first if you like then convert the working version to use param values

using System.Net;
using System.Net.Mail;

var fromAddress = new MailAddress("from@gmail.com", "From Name");
var toAddress = new MailAddress("to@example.com", "To Name");
const string fromPassword = "fromPassword";
const string subject = "Subject";
const string body = "Body";

var _smtpClient = new SmtpClient
           {
               Host = "smtp.gmail.com",
               Port = 587,
               EnableSsl = true,
               DeliveryMethod = SmtpDeliveryMethod.Network,
               UseDefaultCredentials = false,
               Credentials = 
                  new NetworkCredential(fromAddress.Address, fromPassword)
           };
using (var message = new MailMessage(fromAddress, toAddress)
                     {
                         Subject = subject,
                         Body = body
                     })
{
    _smtpClient.Send(message);
}

Answer 4

did you try port 465. may be you can check this article.

http://support.google.com/mail/bin/answer.py?hl=en&answer=13287