Facebook Inactive access token

I am getting a problem, fetching facebook freinds information. When I launch the app, and login to facebook I am able to get friends list. Once, I do quit the app and launch it agai开发者_如何学Gon I am seeing this error : "An active access token must be used to query information about the current user."

though, i had all my facebook info stored in user defaults, I am seeing this.

Strange. Have you echoed your output send to FB.

I have made the experience, that a second reqeust on the same app page will be answered empty, so i store all the Request Data from the first in php Session Vars.

You need to make sure you are resubmitting the access token every time. Are you able to submit the snippet of code you are using? If you are using oauth2 you can use FB.getAccessToken() to retrieve the token in your request.

Edit: realised you tagged iOS so my above answer maybe not relevant. It could be that because you are logged in already, when you revisit, you arent getting a login response, because you haven't just logged in, so the access token is not present? It's hard to know without seeing code. Make sure you are directly getting the token, not relying on the login process to get it