Question

I want to send email using the SMTP client in C#. Currently I am using this code:

System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
message.To.Add("receiver");
message.Subject = "";
message.From = new System.Net.Mail.MailAddress("sender");
message.Body = "This is a test mail";
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");
smtp.Credentials = new System.Net.NetworkCredential("username", "password");
smtp.Port = 587;
smtp.EnableSsl = true;
smtp.Send(message);

But I want to send mail with out using username and password by just providing the sender address. Is this possible in C#?
Is this possible with any SMTP server(Not google). I mean login to server anonymously and just provide your mail address.

Answer 1

No. Gmail does not allow anonymous senders. Thankfully.
If it was possible anyone could pretend to send emails from everyone else, rendering gmail as one big spam engine.