error when uploading video youtube Google API

private void ytAuthenticate()
    {
        myService = new YouTubeService("APPNAME",
                      "DEVKEY");
        myService.setUserCredentials("MyGmail", "PASS");
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        ytAuthenticate();

        YouTubeEntry YoutubeObject = new YouTubeEntry();
        YoutubeObject.Media = new Google.GData.YouTube.MediaGroup();

        YoutubeObject.Media.Title = new MediaTitle("My Test Movie");
        YoutubeObject.Media.Categories.Add(new MediaCategory("Sports", YouTubeNameTable.CategorySchema));
        YoutubeObject.Media.Keywords = new MediaKeywords("cars, funny");
        YoutubeObject.Media.Description = new MediaDescription("My description");
        YoutubeObject.Private = false;
        FormUploadToken token = myService.FormUpload(YoutubeObject);
        Session["form_upload_url"] = token.Url;
        Session["form_upload_token"] = token.Token;
        Response.Redirect("uploader.aspx");
    }