以下是OUT发送域内邮件的
/// <summary>
        /// 调用OutLook发邮件
        /// </summary>
        /// <param name="mailTo"></param>
        /// <param name="subject"></param>
        /// <param name="body"></param>
        public void SentOutLookMail(string from,string mailTo,string cc, string subject, string body)
        {
            CDO.Message CMail = new CDO.Message();
            //设置configuration对象信息   
            CDO.Configuration cf = new CDO.ConfigurationClass();
            //设置sendusing属性   
            cf.Fields["http://schemas.microsoft.com/cdo/configuration/sendusing"].Value = CDO.CdoSendUsing.cdoSendUsingPort;
            cf.Fields["http://schemas.microsoft.com/cdo/configuration/smtpserverport"].Value = 25;
            cf.Fields["http://schemas.microsoft.com/cdo/configuration/smtpserver"].Value = "172.16.0.253";
            cf.Fields.Update();
            CMail.Configuration = cf;
            ////添加邮件回持   
            //if (chkMDN.Checked)
            //    CMail.MDNRequested = true;
            ////添加送达回执   
            //if (chkSended.Checked)
            //    CMail.DSNOptions = CDO.CdoDSNOptions.cdoDSNSuccessFailOrDelay;
            //设置编码   
            CMail.BodyPart.Charset = CDO.CdoCharset.cdoGB2312;
            //发送人   
            CMail.From = from;
            //接收人   
            CMail.To = mailTo;           CMail.Send();        }