Hi, I am posting here in case one of you got this error. It's an old bug in my game that I was never able to solve. I use happstack-authenticate, but when I select facebook to login with, I get: FacebookException {fbeType = " ()", fbeMessage = ""} However, it seems well configured. I put: facebookAuth = Credentials {appName = "Nomyx", appId = "161007670738608", appSecret = <my secret>} On the facebook website, I have the application configured: application Id: 161007670738608 secret key: <my secret> Display Name: Nomyx NameSpace: nomyx-app App Domains: www.nomyx.net URL: http://www.nomyx.net:8000/ Do you have any hints? Thanks a lot!! Corentin http://www.nomyx.net:8000