how send a mail in asp.net using c#

[ramamoorthy]

hello

i want mail server in asp.net using c#


try
{
SmtpClient sm = new SmtpClient();
sm.Host = "localhost";
MailMessage m = new MailMessage();
m.To.Add("[e-mail]");
m.From = new MailAddress("[e-mail]");
//m.To.Add(new MailAddress(to.Text.ToString()));
//m.From = new MailAddress(from.Text.ToString());
m.Subject = subject.Text.ToString();
m.Body = body.Text.ToString();
sm.Send(m);
Label1.Text = "mail sent";
}
catch (SmtpException ex)
{
Label1.Text = ex.Message;
}
this is my program but the mail not send because

the error is

Mailbox unavailable. The server response was: 5.7.1 Unable to relay for [e-mail]

[radcaesar]

sm.Host = "localhost";, This line cause the problem. It means ur own system is the SMTP Mail server. But ur using Google to send mail.

use smtp.google.com as ur SMTP server.