when i send mail on button click then error show:
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required my code:-
MailMessage msg = new MailMessage(); msg.From = new MailAddress("test@gmail.com"); msg.To.Add("test@gmail.com"); msg.Subject = "test"; msg.Body = "Test Content"; //msg.Priority = MailPriority.High; using (SmtpClient client = new SmtpClient()) { client.EnableSsl = true; client.UseDefaultCredentials = false; client.Credentials = new NetworkCredential("test@gmail.com", "mypassword"); client.Host = "smtp.gmail.com"; client.Port = 587; client.DeliveryMethod = SmtpDeliveryMethod.Network; ...

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