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("[e-mail]", "[e-mail]", "test", "testbody");
// I also tested like this
// client.Send("[e-mail]", "[e-mail]", "test", "testbody");

But this code works

var client = new SmtpClient("smtp.gmail.com", 587)
{
    Credentials = new NetworkCredential("username", "password"),
    EnableSsl = true
};
client.Send("[e-mail]", "[e-mail]", "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