无法在Unity3D中的手机中发送电子邮件？

Question

I Need to Send Mail by Using mobile,the below code sends mail in systems but not send mail in mobiles.i dont understand the problem, plz help me how to send mail in mobiles.i'm using this in Andriod mobiles.

My code is:

using System;
using System.IO;
using System.Collections.Generic;
using System.Net;
using System.Linq;
using System.Text;
using System.Net.Mail;
using UnityEngine;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;


public class EmailHandler : ScriptableObject
 {

     public static void SendEmail()
     {
       try
         {

        string smtp_Name;
        int port_no;
        string toAddr = "ToMailAddress@gmail.com";
        MailMessage mail = new MailMessage();
        //From address to send email
         mail.From = new MailAddress("From@gmail.com");
        //To address to send email
        mail.To.Add(toAddr);
        mail.Subject = "TEST for UNITY3D...!!!!!!";
        mail.Body = "This is a test mail from C# program";


            smtp_Name = "smtp.gmail.com";
            port_no = 587;


        SmtpClient smtpC = new SmtpClient(smtp_Name);
        smtpC.Port = port_no;

        //Credentials for From address
        smtpC.Credentials =(System.Net.ICredentialsByHost) new System.Net.NetworkCredential("Email", "Password") as ICredentialsByHost;
        smtpC.EnableSsl = true;
     ServicePointManager.ServerCertificateValidationCallback = 
            delegate(object s, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) 
                { return true; };
        smtpC.Send(mail);

        //Change Console.Writeline to Debug.Log 
        Debug.Log ("Message sent successfully");
    }
    catch (Exception e)
    {
        Debug.Log(e.GetBaseException());
        //You don't need or use Console.ReadLine();
    }
  }  
 }

Answer 1

in line

attachment = new System.Net.Mail.Attachment("attachment");

whats "attachment"???

you have to specify a file name like this...

attachment = new System.Net.Mail.Attachment("mifile.pdf");