Deserialization of CriteriaBase class

Hi Rocky,

I have spent almost 20 hours on this issue. Can you help me please?

I am trying to serialize and deserialize a class called ReturnCriteria which is inherited from CSLA.CriteriaBase.
The serialization is working fine and I have seen the xml. This is the method  for serialization:

        public static void SaveData<T>(string guid, T data)
        {
            DeleteData();
            using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
            {
                using (IsolatedStorageFileStream isfs = new IsolatedStorageFileStream(guid, FileMode.Create, isf))
                {
                    XmlWriterSettings settings = new XmlWriterSettings();
                    settings.NewLineChars = string.Empty;
                    settings.Indent = false;
                    settings.NewLineHandling = NewLineHandling.None;
                    using (XmlWriter xmlwriter = XmlWriter.Create(isfs, settings))
                    {
                        XmlSerializerNamespaces namespaces = new XmlSerializerNamespaces();
                        namespaces.Add(string.Empty, string.Empty);
                        XmlSerializer serializer = new System.Xml.Serialization.XmlSerializer(typeof(T));
                        serializer.Serialize(xmlwriter, data, namespaces);
                    }
                }
            }
        }


But for deserialization it gives me an exception:

{System.Security.VerificationException: Operation could destabilize the runtime.
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderTaxReturnListControllerCriteria.Read5_Item(Boolean isNullable, Boolean checkType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderTaxReturnListControllerCriteria.Read6_Item()}

Here is the code for Deserialization:

        private static T LoadData<T>(string guid)
        {
            T data = default(T);
            using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
            {
                try
                {
                    using (IsolatedStorageFileStream isfs = new IsolatedStorageFileStream(guid, FileMode.Open, isf))
                    {
                        XmlSerializer serializer = new System.Xml.Serialization.XmlSerializer(typeof(T));
                        var obj = serializer.Deserialize(isfs);
                    }
                }
                catch
                {
                }
            }

            return data;
        }

Note: This code is saving and retreiving the data from IsolatedStorage of silverlight.