title: Facebook iOS SDK 3.1: "Error: HTTP status code: 400"
body: <p>I am running the Facebook SDK 3.1 on Xcode 4.5GM with iOS6 simulator. I connect to FB in the iOS settings and successfully FB connect in my app using the new iOS6 FBConnect UI. I have an access token, can see my friends, send app requests, post to my wall, etc. However, every time I initiate any sort of FBURLConnection is made, I see this printed to my console:</p>
  
  <pre><code>Error: HTTP status code: 400
  </code></pre>
  
  <p>I went into the FB code and printed the reponse when this error is printed and I get:</p>
  
  <pre><code>{
      body =     {
          error =         {
              code = 100;
              message = "(#100) The parameter 'attribution' is required for the 'mobile_app_install' activity";
              type = OAuthException;
          };
      };
      code = 400;
  }
  </code></pre>
  
  <p>Does anyone know how to resolve this? All functionality seems to work, but I keep seeing this spam my console.</p>