c# 通过163邮箱发送邮件

            MailMessage msg = new MailMessage();
                msg.Subject = "测试";   //标题
                msg.Body = " 测试,测试";    //内容
                msg.From = new MailAddress("163邮箱");
                msg.To.Add("发送地址");
                SmtpClient client = new SmtpClient();
                client.Host = "smtp.163.com";   //发件方服务器地址
                client.Port = 25;  //发件方端口
                client.UseDefaultCredentials = true;
                NetworkCredential credential = new NetworkCredential("163邮箱", "密码");
                client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
                credential.UserName = "用户名";
                credential.Password = "密码";
                client.Credentials = credential;
                client.Send(msg);