WP8 HttpWebRequest访问Scoreoid时总是返回NotFound

我正在尝试使用Windows Phone 8 Emulator访问Scoreoid API上的身份验证。但我在这里没有任何成功。我不得不说，虽然Http不是我喜欢的，我希望这里的人可能会发现我的代码有任何错误！我一直得到"远程服务器返回了一个错误：NotFound，代码如下：

             string baseUri = "https://api.scoreoid.com/v1/getPlayer";
        HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.Create(baseUri);
        webRequest.Method = "POST";
        // What we are sending
        string postData = String.Format("api_key={0}&game_id={1}&response={2}&username={3}",
                HtmlEncode(apiKey),
                HtmlEncode(gameID),
                HtmlEncode("XML"),
                HtmlEncode(name));
        // Turn our request string into a byte stream
        byte[] postBuffer = Encoding.UTF8.GetBytes(postData);
        // This is important - make sure you specify type this way
        webRequest.ContentType = "application/x-www-form-urlencoded";
        int timeoutInterval = 30000;
        DateTime requestDate = DateTime.Now;
        Timer timer = new Timer(
        (state) =>
        {
            if ((DateTime.Now - requestDate).TotalMilliseconds >= timeoutInterval)
                webRequest.Abort();
        }, null, TimeSpan.Zero, TimeSpan.FromMilliseconds(1000));
        //webRequest.ContentLength = postBuffer.Length;
        //webRequest.KeepAlive = false;
        //webRequest.ProtocolVersion = HttpVersion.Version10;
        try
        {
            webRequest.BeginGetRequestStream(
            requestAsyncResult =>
            {
                try
                {
                    HttpWebRequest request = ((HttpWebRequest)((object[])requestAsyncResult.AsyncState)[0]);
                    byte[] buffer = ((byte[])((object[])requestAsyncResult.AsyncState)[1]);
                    Stream requestStream = request.EndGetRequestStream(requestAsyncResult);
                    requestStream.Write(buffer, 0, buffer.Length);
                    requestStream.Close();
                    requestDate = DateTime.Now;
                    request.BeginGetResponse((state) =>
                    {
                        timer.Change(Timeout.Infinite, Timeout.Infinite);
                        HttpWebResponse response = null;
                        try
                        {
                            Debug.WriteLine("Before call to response = HttpWebResponse: ");
                            response = (HttpWebResponse)((HttpWebRequest)state.AsyncState).EndGetResponse(state);
                            Debug.WriteLine("HttpWebResponse: " + response);
                            if (response.StatusCode == HttpStatusCode.OK)
                            {
                                // If the request success, then call the success callback
                                // or the failed callback by reading the response data
                                using (Stream stream = response.GetResponseStream())
                                {
                                    try
                                    {
                                        XDocument xdoc = XDocument.Load(stream);
                                        // Data contains error notification.
                                        if (xdoc.Root.Name == "error")
                                            throw new InvalidOperationException(xdoc.Root.Value);
                                        //success(xdoc);
                                    }
                                    catch (Exception ex)
                                    {
                                        //failed(ex.Message);
                                    }
                                    stream.Close();
                                }
                            }
                            else
                            {
                                // If the request fails, then call the failed callback
                                // to notfiy the failing status description of the request
                                //failed(response.StatusDescription);
                                Debug.WriteLine("Exception: " + response);
                            }
                        }
                        catch (Exception ex)
                        {
                            // If the request fails, then call the failed callback
                            // to notfiy the failing status description of the request
                            //failed("Unknown HTTP error.");
                            Debug.WriteLine("Exception1: " + ex.Source);
                        }
                        finally
                        {
                            request.Abort();
                            if (response != null)
                                response.Close();
                        }
                    }, request);
                }
                catch (Exception ex)
                {
                    // Raise an error in case of exception
                    // when submitting a request
                    //failed("Unknown HTTP error.");
                    Debug.WriteLine("exception2 " + ex.Message);
                }
            }, new object[] { webRequest, postBuffer });
        }
        catch (Exception ex)
        {
            // Raise an error in case of exception
            // when submitting a request
            //failed("Unknown HTTP error.");
            Debug.WriteLine("Exception3 " + ex.Message);
        }
    }

代码总是以exception1块结束，该块包含以下内容：

堆栈跟踪：

位于System.Net.Browser.AncHelper.BeginOnUI（SendOrPostCallback beginMethod，对象状态）位于System.Net.Browser.ClientHttpWebRequest.EndGetResponse（IAsyncResult-asyncResult）位于ContosoSocial.OpenXLive。<>c_DisplayClass4。<>c_DisplayClass6.b_2（IAsyncResult状态）

信息：

远程服务器返回错误：NotFound。

我在WMAppManifest中启用了网络功能，所有地址都定义正确，并已部署到手机上，但我很困惑？

非常感谢您抽出时间