I need send mail using gmail with SMTP. But it shows an error

I am developing website in ASP.net,in that page Code was given below it works Localhost only not in Web server.What can i do?? Please Anyone can help me?


It shows an error,

Quote:

The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.

What I have tried:

My Code is,
 protected void btnSubmit_ServerClick(object sender, EventArgs e)
    {
        SmtpClient client = new SmtpClient();
        client.Host = "smtp.gmail.com"; //Set your smtp host address  
        client.Port = int.Parse("587"); // Set your smtp port address  
        client.DeliveryMethod = SmtpDeliveryMethod.Network;
        client.Credentials = new NetworkCredential("From@gmail.com", "****"); 
        client.EnableSsl = true; // Set SSL = true  
        MailMessage message = new MailMessage();
        message.To.Add("svrcrackers@gmail.com"); // Add Receiver mail Address  
        message.From = new MailAddress("From@gmail.com"); // Sender address  
        message.Subject = "EnQuiry From Customer";

        message.IsBodyHtml = true; //HTML email  
        message.Body = txtsubject.Text + "<br/>" + txtName.Text + "<br/>" + txtMobileNo.Text;

        client.Send(message);
        Response.Write("<script>alert('Submitted Successfully');</script>");
        Clear();
        }

Tags: C#