I am dealing with the same problem written in previous article ( Loginned, but passport not deserializing ) Trial 2) Setting CORS in Server > link1 ) https://ko.javascript.info/fetch-crossorigin > link2 ) http://guswnsxodlf.github.io/enable-CORS-on-express Let's See what CORS is CORS = Cross-Origin-Resourse-Sharing * What is Origin(출처) one url such as (www.google.com) seems like one componenent but is is comprised of multiple components ![](https://images.velog.io/images/dhs