反序列化.Pages.Response类型的对象时出错。 ' PVTLTD'包含无效的UTF8字节

Question

HttpWebRequest request = WebRequest.Create(requestUrl) as HttpWebRequest;
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
    if (response.StatusCode != HttpStatusCode.OK)
        throw new Exception(String.Format(
        "Server errOr (HTTP {0}: {1}).",
        response.StatusCode,
        response.StatusDescription));
    DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(typeof(Clari5AppWeb.Pages.Response));
    object objResponse = jsonSerializer.ReadObject(response.GetResponseStream());
    Response jsonResponse = objResponse as Response;
    return jsonResponse;

请解决;仅对某些搜索值，它会给出错误。