Facebook App Stopped Posting To Page Wall (user does not have sufficient administrative permission)

Question

Since 6th November, my application has once again stopped posting to the wall throwing an authorisation error. I use C# SDK with the following code:

public static void postItemToWall(Item MyItem)
{

            String URL = "http://myurl";
            dynamic parameters = new ExpandoObject();

            parameters.message = "My Message"

            Facebook.FacebookClient app = new Facebook.FacebookClient(app_token);

            var result = app.Post("/pageid/feed", parameters);

 }    

The application now throws the following exception:

(OAuthException - #200) (#200) User does not have sufficient administrative permission for this action on this page. For reference I am page manager. The app has post to wall permissions and I can using the same bit of script retrieve feed posts.

This worked up until 6th November 2012, and is the third instance this year where something has caused my app to fall over, from FB side. The permissions are all checked and I have manager access to said page.

Any thoughts would be appreciated.

Answer 1

After much trying and Anveshs' pointer to the graph explorer, i did some more scenario based testing I discovered that for whatever reason the APP_TOKEN ceased working on the 6th of November, however using my USER_TOKEN, it works again. As its an offline token I've no issue with toke expirity.