System.net发邮件
公司要求在程序中出现某个错误时，发邮件给管理员，以下是我写的发邮件方法（以QQ邮箱为例吧），运行时不报错，但是邮件没发出去。请各位高手帮忙看下，本人菜鸟，第一次接触.net。

#region 发邮件
public static void sendMail(ReturnEntity re)
{
AdminEmail email = new AdminEmail();
email.To = ConfigurationManager.AppSettings["to"];//XXXX@qq.com
email.From = ConfigurationManager.AppSettings["from"];//yyy@qq.com
email.UserName = ConfigurationManager.AppSettings["userName"];//yyy@qq.com
email.Password= ConfigurationManager.AppSettings["password"];//123456
email.DisplayName = ConfigurationManager.AppSettings["displayName"];
email.Subject = "FORM_NUM的单据同步EFT状态出错";
email.Message = re.ErrorDesc;

try
{
MailMessage msg = new MailMessage();
msg.Body = email.Message;//邮件的内容
msg.Subject = email.Subject;//邮件的主题
msg.From = new MailAddress(email.From,"",Encoding.Default);//发件人得地址
msg.To.Add(email.To);//收件人的地址
SmtpClient client = new SmtpClient();
client.UseDefaultCredentials = true;
client.Port = 25;
client.Credentials = new NetworkCredential(email.UserName,email.Password);
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.Host = "smtp.qq.com";
object obj = msg;
client.SendAsync(msg,msg);
}
catch(Exception ex)
{
throw new Exception(ex.Message);
}

}
#endregion

[解决办法]
这个发邮件不稳定就是，应该是没什么问题，看看是不是进了垃圾邮件。。。

下面是一种发邮件的方式，以前用过的，建议用用Jmail

C# code

  #region                public static void Sends(string email)         {            string formto = "发件箱地址";            string to = email;   //接收邮箱            string content = "";            string body = "";            string name = "发件箱";            string upass = "密码";            string smtp = "smtp地址";            SmtpClient _smtpClient = new SmtpClient();                        _smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;//指定电子邮件发送方式            _smtpClient.Host = smtp; //指定SMTP服务器            _smtpClient.Credentials = new System.Net.NetworkCredential(name, upass);//用户名和密码            MailMessage _mailMessage = new MailMessage();            //发件人，发件人名             _mailMessage.From = new MailAddress(formto, "别名");            //收件人             _mailMessage.To.Add(to);            _mailMessage.SubjectEncoding = System.Text.Encoding.GetEncoding("gb2312");            _mailMessage.Subject = content;//主题            _mailMessage.Body = body;//内容            _mailMessage.BodyEncoding = System.Text.Encoding.GetEncoding("gb2312");//正文编码            _mailMessage.IsBodyHtml = true;//设置为HTML格式            _mailMessage.Priority = MailPriority.High;//优先级               try            {                _smtpClient.Send(_mailMessage);            }            catch (Exception)            {                                            }                    }        #endregion