Windows Service Use Isolated Storage

Question

I have a windows service which seems to be unable to use isolated storage (most likely because I'm doing something wrong). The service is running under local system. Everytime I run the code there is no change to isolated storage folder. Can someone please tell me why this is so. I have tried on windows 7 and windows 8.1

IsolatedStorageFileStream configFile = new IsolatedStorageFileStream("UIsolate.cfg", FileMode.Create);

            // create a writer to write to the stream
            StreamWriter writer = new StreamWriter(configFile);

            // write some data to the config. file

            writer.WriteLine("test");

            // flush the buffer and clean up
            sr.Close();
            writer.Close();
            configFile.Close();