Heroku: Failed to lookup view "index.jade" in views directory "/app/server/views"

I started a new nodejs project on Heroku. The code works on my machine just fine but when I run it on Heroku I get this message:

Failed to lookup view "index.jade" in views directory "/app/server/views"

Knowing that I DO HAVE the "index.jade" file in directory "/app/server/views".

OS :windows 10.

Server.js File

var express = require('express');
var path = require ('path');
var connectionString = "mongodb://localhost:27017/TravelWithMe";

stylus = require ('stylus');

logger = require('morgan');
bodyParser = require('body-parser');
mongoose = require('mongoose');
var app = express();

function compile   (str,path)
{
    return stylus(str).set('filename',path);
}

app.set('views',path.join(__dirname ,'server/views'));
app.set('view engine', 'jade');
app.use(logger('dev'));


app.use(bodyParser.urlencoded({extended:true}));
app.use(bodyParser.json());

app.use(stylus.middleware(
    {
        src: path.join(__dirname ,'public'),
        compile: compile
    }
));


app.use(express.static(path.join(__dirname ,'public')));

mongoose.connect(connectionString);
var db = mongoose.connection;
db.on('error',console.error.bind(console,'connection error ...'));
db.once('open',function callback() {
console.log('TWM Db opened')
}); 

app.get('/partials/:partialPath', function(req, res) {
    res.render('partials/' + req.params.partialPath);
});

app.get('*',function (req,resp){
    resp.render('index.jade',{MongoMessage : MongoMessage});
});

var port = process.env.PORT || 3030;
app.listen(port);

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