Setting up FormsAuthentication after SSO authentication

Question

My ASP.NET MVC 4 application is protected by SSO (OAM) with an ISAPI filter running on IIS. When a request to my application is received, it is intercepted by ISAPI filter a

Answer 1

I had to explicitly kill the session inside Session_Start if requested URL is logout URL. And then with next request (like from logout to login page again), it generates a new session and runs smoothly.

protected void Session_Start()
    {
        if (!Request.IsAuthenticated && !IsSignoutURL)
            AcceptSessionRequest(); //process local authentication

        else if (IsSignoutURL)
            RejectSessionRequest(); //kill the sessions
    }

For background on how SSO passes authenticated user's identity to my application, read my comment to tvanfosson's post.

The post remains opened for a better idea.