I have a client and server, client sending file to server. When i transfer files on my computer(in local) everything is ok(try to sen file over 700mb).

When i try to sent file use Internet to my friend in the end of sending appears error on server "Input string is not in correct format".This error appears in this expression fSize = Convert::ToUInt64(tokenes[0]); - and i don't mind wht it's appear. File should be transfered and wait other transferring

ps: sorry for too much code, but i want to find solution

private: void CreateServer()
   {

    try{
     IPAddress ^ipAddres = IPAddress::Parse(ipAdress);
     listener = gcnew System::Net::Sockets::TcpListener(ipAddres, port);
     listener->Start();
     clientsocket =listener->AcceptSocket();
     bool keepalive = true;
     array<wchar_t,1> ^split = gcnew array<wchar_t>(1){ '\0' };
     array<wchar_t,1> ^split2 = gcnew array<wchar_t>(1){ '|' };

     statusBar1->Text = "Connected" ;
     //
     while (keepalive)
     {
      array<Byte>^ size1 = gcnew array<Byte>(1024); 
      clientsocket->Receive(size1);
      System::String ^notSplited = System::Text::Encoding::GetEncoding(1251)->GetString(size1);

      array<String^> ^ tokenes = notSplited->Split(split2);
      System::String ^fileName = tokenes[1]->ToString();
      statusBar1->Text = "Receiving file" ; 
      unsigned long  fSize = 0;


                             //IN THIS EXPRESSIN APPEARS ERROR 
      fSize = Convert::ToUInt64(tokenes[0]);

      if (!Directory::Exists("Received"))
       Directory::CreateDirectory("Received");

      System::String ^path = "Received\\"+ fileName;
                      while (File::Exists(path))
      {
       int dotPos = path->LastIndexOf('.');
       if (dotPos == -1)
       {
        path += "[1]";
       }
       else
       {
        path = path->Insert(dotPos, "[1]");
       }
      }

      FileStream ^fs = gcnew FileStream(path, FileMode::CreateNew, FileAccess::Write);
      BinaryWriter ^f = gcnew BinaryWriter(fs);
       //bytes received
      unsigned long processed = 0;

      pBarFilesTr->Visible = true;
      pBarFilesTr->Minimum = 0;
      pBarFilesTr->Maximum = (int)fSize;
      // Set the initial value of the ProgressBar.
      pBarFilesTr->Value = 0; 
      pBarFilesTr->Step = 1024;

      //loop for receive file
      array<Byte>^ buffer = gcnew array<Byte>(1024); 
      while (processed < fSize) 
      {
       if ((fSize - processed) < 1024)
       {
        int bytes ;
        array<Byte>^ buf = gcnew array<Byte>(1024); 
        bytes = clientsocket->Receive(buf);
        if (bytes != 0)
        {
         f->Write(buf, 0, bytes);
         processed = processed + (unsigned long)bytes;
         pBarFilesTr->PerformStep();
        }
        break;                            
       }
       else
       {
        int bytes = clientsocket->Receive(buffer);
        if (bytes != 0)
        {
         f->Write(buffer, 0, 1024);
         processed = processed + 1024;
         pBarFilesTr->PerformStep();
        }
        else break;
       }                        
      }

      statusBar1->Text = "File was received" ;
      array<Byte>^ buf = gcnew array<Byte>(1); 
      clientsocket->Send(buf,buf->Length,SocketFlags::None);
      f->Close();
      fs->Close();
      SystemSounds::Beep->Play();
     }
    }catch(System::Net::Sockets::SocketException ^es)
    {
     MessageBox::Show(es->ToString());
    }
    catch(System::Exception ^es)
    {
     MessageBox::Show(es->ToString());
    }
   }

private: void CreateClient()
{

                       clientsock = gcnew System::Net::Sockets::TcpClient(ipAdress, port);
                       ns = clientsock->GetStream();
  sr = gcnew StreamReader(ns);
  statusBar1->Text = "Connected" ;

}

private:void Send()
   {
    try{
     OpenFileDialog ^openFileDialog1 = gcnew OpenFileDialog();
     System::String ^filePath = "";
     System::String ^fileName = "";

     //file choose dialog
     if (openFileDialog1->ShowDialog() == System::Windows::Forms::DialogResult::OK)
     {
      filePath = openFileDialog1->FileName; 
      fileName = openFileDialog1->SafeFileName;
     }
     else
     {
      MessageBox::Show("You must select a file", "Error",
       MessageBoxButtons::OK, MessageBoxIcon::Exclamation);
      return;
     }
     statusBar1->Text = "Sending file" ; 

     NetworkStream ^writerStream = clientsock->GetStream();
     System::Runtime::Serialization::Formatters::Binary::BinaryFormatter ^format = 
      gcnew System::Runtime::Serialization::Formatters::Binary::BinaryFormatter();

     array<Byte>^ buffer = gcnew array<Byte>(1024);
     FileStream ^fs = gcnew FileStream(filePath, FileMode::Open);
     BinaryReader ^br = gcnew BinaryReader(fs);
                 //file size
     unsigned long fSize = (unsigned long)fs->Length;
     //transfer file size + name
     bFSize = Encoding::GetEncoding(1251)->GetBytes(Convert::ToString(fs->Length+"|"+fileName+"|"));
     writerStream->Write(bFSize, 0, bFSize->Length);

     //status bar
     pBarFilesTr->Visible = true;
     pBarFilesTr->Minimum = 0;
     pBarFilesTr->Maximum = (int)fSize;
     pBarFilesTr->Value = 0; // Set the initial value of the ProgressBar.
     pBarFilesTr->Step = 1024;

                 //bytes transfered
     unsigned long processed = 0; 
     int bytes = 1024;
     //loop for transfer
     while (processed < fSize) 
     {
      if ((fSize - processed) < 1024)
      {
       bytes = (int)(fSize - processed);
       array<Byte>^ buf = gcnew array<Byte>(bytes);
       br->Read(buf, 0, bytes);

       writerStream->Write(buf, 0, buf->Length); 
       pBarFilesTr->PerformStep();
       processed = processed + (unsigned long)bytes;
       break;
      }
      else
      {
       br->Read(buffer, 0, 1024);
       writerStream->Write(buffer, 0, buffer->Length);
       pBarFilesTr->PerformStep();
       processed = processed + 1024;
      }               
     }
     array<Byte>^ bufsss = gcnew array<Byte>(100);
     writerStream->Read(bufsss,0,bufsss->Length);

 statusBar1->Text = "File was sent" ;
 btnSend->Enabled = true;
 fs->Close();
 br->Close();
 SystemSounds::Beep->Play();
 newThread->Abort();
 }
 catch(System::Net::Sockets::SocketException ^es)
 {
  MessageBox::Show(es->ToString());
 }
  }