使用Sysdate.Net.Mail送Mail
我的如何送出去的MAIL,在接收到MAIL的人不可以再寄封MAIL.

下面是正常送MAIL的Function:
public void SendMailUseSMTP(string subject, string MailHost, string MailFrom, string MailFromPassWord, string MailTo, string MailCc, string text, string AttachmentsName, bool IsBodyHtml)
{
try
{
MailMessage msg = new MailMessage();
string[] To = MailTo.Split(';');
for (int i = 0; i < To.Length; i++)
{
msg.To.Add(To[i]);
}

string[] CC = MailCc.Split(';');
for (int j = 0; j < CC.Length; j++)
{
msg.CC.Add(CC[j]);
}
msg.From = new MailAddress(MailFrom, MailFrom, System.Text.Encoding.UTF8);
msg.Subject = subject;
msg.SubjectEncoding = System.Text.Encoding.UTF8;
msg.Body = text;
msg.BodyEncoding = System.Text.Encoding.UTF8;
msg.IsBodyHtml = IsBodyHtml;
msg.Priority = MailPriority.High;
if (AttachmentsName != "")
{
msg.Attachments.Add(new Attachment(AttachmentsName));
}

SmtpClient client = new SmtpClient();
client.Credentials = new System.Net.NetworkCredential(MailFrom, MailFromPassWord);
client.Host = MailHost;
object userState = msg;

client.SendAsync(msg, userState);
}
catch (System.Net.Mail.SmtpException ex)
{
throw new Exception("SendMailUseSMTP Subject:" + subject + " Exception:" + ex.Message);
}
}

[解决办法]
接收mail的帐号