Talk:FQL:standard user info
From Facebook Developer Wiki (FbDevWiki.com)
Note:
You cannot query this table for a desktop application or in the context of a session secret-based session.
aka Exception: 15: The method you are calling must be called with an app secret signed session
What shout that mean?
How can we get over this?
Answer
It sounds like you're trying to use the regular user session (the access token / session associated with the current user). The error indicates that you can't do that, and can only use an application signed access token. If you're using the PHP SDK, you can try calling the setSession() method with no arguments to clear out the current session and force it to use the application signed access token instead.
$fb = new Facebook(array( 'appId' => $appid, 'secret' => $appsecret, )); $fb->setSession(); // do your FQL query after here...