C#调用邮箱smtp

static string accountName = System.Configuration.ConfigurationManager.AppSettings["mailAccountName"];

    static string password = System.Configuration.ConfigurationManager.AppSettings["mailPassword"];
    static string smtpServer = System.Configuration.ConfigurationManager.AppSettings["mailSmtpServer"];
    static int smtpPort = int.Parse(System.Configuration.ConfigurationManager.AppSettings["mailSmtpPort"]);
    static string displayName= System.Configuration.ConfigurationManager.AppSettings["mailDisplayName"];
    static string userState= System.Configuration.ConfigurationManager.AppSettings["mailUserState"];

    static public void SendMail(string sendTo, string subject, string body)
    {
        try
        {
            // Command line argument must the the SMTP host.
            SmtpClient client = new SmtpClient(smtpServer, smtpPort);
            client.UseDefaultCredentials = true;
            client.DeliveryMethod = SmtpDeliveryMethod.Network;
            client.Credentials = new NetworkCredential(accountName, password);
            
            // Specify the e-mail sender.
            // Create a mailing address that includes a UTF8 character
            // in the display name.
            MailAddress from = new MailAddress(accountName,
               displayName,
            System.Text.Encoding.UTF8);
            // Set destinations for the e-mail message.
            MailAddress to = new MailAddress(sendTo);
            // Specify the message content.
            MailMessage message = new MailMessage(from, to);
            message.Body = body;
            // Include some non-ASCII characters in body and subject.
            string someArrows = "(请勿回复这封邮件)";
            message.Body += Environment.NewLine + someArrows;
            message.BodyEncoding = System.Text.Encoding.UTF8;
            message.Subject = subject;
            message.SubjectEncoding = System.Text.Encoding.UTF8;
            client.Send(message);

            message.Dispose();
            client.Dispose();
        }
        catch { }
    }      

还是不行，现在我换了阿里API接口好了

您好，

里边的：

new SmtpClient("smtpdm.aliyun.com", 25);

是否应该为：

new SmtpClient("smtp.dm.aliyun.com", 25);