Activity does not open after thread

Question

I’m on an Android project and I have an Activity that doesn’t open, well starting from my main Activity I already have a button that calls another and everything occurs as expected I can make the transition from one to another without problems but I do not know what happens with this other that I call no more appears, I have already exchanged it with the one that is being called and then it appears, much more we go to the events so that if someone can help me... I have a WS and in my main Activity two fields user and password, When I click on the login button I call a thread that will access WS if I can log in then I have to call Sincronizaractivity, this has the purpose of doing a synchronization or import some entries but it does not appear and even in the logcat something indicates an error. Well a little code might explain it better.

private void login(String login, String senha) {
    soap = new SoapObject(namespace,METHOD_NAME ); 

    PropertyInfo p1 = new PropertyInfo();
    PropertyInfo p2 = new PropertyInfo();
    p1.setName("Usuario");
    p1.setValue(login);
    p1.setType(String.class);
    p2.setName("Senha");
    p2.setValue(senha);
    p2.setType(String.class);

    soap.addProperty(p1);
    soap.addProperty(p2);

    envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
    envelope.setOutputSoapObject(soap);
    transporte = new AndroidHttpTransport(URL);

    progress = ProgressDialog.show(MainActivity.this, "Logando", "Aguarde...", true, false);

    Thread th = new Thread(MainActivity.this);
    th.start();
}

@Override
public void run() {

    try {

        transporte.call("", envelope);
        //resposta = (SoapPrimitive) envelope.getResponse();
        objRetorno = envelope.getResponse();

        handler.sendEmptyMessage(0);

    } catch (Exception e) {
        Log.e("Erro", "Erro: "+ e.getMessage());
        finish();
    }

}

private Handler handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {

        progress.dismiss();

        String[] parts = objRetorno.toString().split("#");

        if (Boolean.parseBoolean(parts[0])) {
            edtRetorno.setText("Ok ! "+parts[2]);
            criarsessao(parts);
        } else {
            edtRetorno.setText("Acesso negado! "+parts[1]);
        }

    }
};

Well and to finish the method that calls Activity

private void criarsessao(String[] dados){
    sessaoUsuario = new SessaoUsuario();

    sessaoUsuario.setUsuario(edtUserName.getText().toString());
    sessaoUsuario.setSenha(edtPassWord.getText().toString());
    sessaoUsuario.setId(Integer.parseInt(dados[1]));
    sessaoUsuario.setNome(dados[2].toString());

    sessaoUsuarioService.criarSessao(sessaoUsuario);

    config = confService.BuscaporId(1);

    if (config.getSinc().toString() == "S"){
        Intent intent = new Intent(MainActivity.this, SincronizarActivity.class);
        startActivity(intent);
    }

}

So if anyone can give me a helping hand I’d appreciate it.