Open index.js (in your case it may be app.js or server.js) and set the request header
var express = require('express'); var app = express(); ... ... //CORS support settings app.use(function(req, res, next){ res.header('Access-Control-Allow-Origin', '*'); res.header('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept'); res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE'); next(); }); ... .... app.get('/', (req, res) => { res.sendFile(__dirname + '/index.html'); }); app.use('/api/user', user); ...