Send Error:不允许使用邮箱名称。 服务器响应为: You are not authorized to send mail, authentication is required

使用asp.net 2.0 中新的System.Net.Mail发送邮件，使用163邮件服务器时等其他服务器时可能会出现：“Send Error:不允许使用邮箱名称。 服务器响应为: You are not authorized to send mail, authentication is required”错误，以下程序中红色为特别需要主要的地方。


protected void Button1_Click(object sender, EventArgs e)




...{


System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();


//收件人


message.To.Add(txtMailAddress.Text);


//抄送


foreach(string mailAddress in txtCopyAddress.Text.Split(','))




...{


if (!string.IsNullOrEmpty(mailAddress))




...{


message.CC.Add(mailAddress);


}


}


//主题


message.Subject = txtSubject.Text;




message.From = new System.Net.Mail.MailAddress(fromAddress);


message.Body = txtMailContents.Text;


//发送附件


if (fulAttachment.HasFile)




...{


System.Net.Mail.Attachment attachment = new System.Net.Mail.Attachment(fulAttachment.PostedFile.FileName);


message.Attachments.Add(attachment);


}


System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient(txtSMTPAddress.Text);


smtp.Credentials = new System.Net.NetworkCredential(txtUserName.Text,txtPassword.Text);




//smtp.usedefaultcredentials = true;




try




...{


smtp.Send(message);


lblReturnMessage.Text = "Mail Send Success!";


}


catch (System.Net.Mail.SmtpException ex)




...{


lblReturnMessage.Text = "Send Error:" + ex.Message;


}


}

如果选择了163的SMTP服务器,“smtp.163.com”，发件人必须是登录用户的163 email用户地址。


System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.163.com");


smtp.Credentials = new System.Net.NetworkCredential("163emailaddress","emailpassword");




System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();


message.From = new System.Net.Mail.MailAddress("163emailaddress@163.com");