myMail = new MailMessage();
this.myMail.Subject = this.txtCaption.ToString();
this.myMail.From = this.txtSender.ToString();
this.myMail.To = this.txtReceive.ToString();
this.myMail.Body = this.txtContent.ToString();
this.myMail.Priority = MailPriority.High;
this.myMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate",1);
this.myMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername","[email protected]"); 
this.myMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword","******")
System.Web.Mail.SmtpMail.SmtpServer = "smtp.163.com";
System.Web.Mail.SmtpMail.Send(this.myMail);总是说无法发送邮件