I’ve started a simple facebook iframe application. I created a handler to deal with the deauthorize callback (ashx) with the following code:
FacebookSignedRequest signedRequest = FacebookSignedRequest.Parse(appSecret,context.Request.Form["signed_request"]);
//flag signedRequest.UserId as inactive;
Why isn’t Facebook calling my callback that I specified in the app settings?
Facebook will call that callback when a user has removed your application from his list of apps at http://www.facebook.com/settings?tab=applications. Are you sure your URL is publicly accessible? Are you sure you don’t need any cookies to access the callback?