New Post: The request is not supported 0x80070032

I am having the same problem connecting to a 2003 Server
The request is not supported. (Exception from HRESULT: 0x80070032)

my code is fairly simple, I'm just trying to connect at the moment

string strUsername = ConfigurationManager.AppSettings["Username"];
            string strPassword = ConfigurationManager.AppSettings["Password"];
            string strServer = ConfigurationManager.AppSettings["Server"];
            string strDomain = ConfigurationManager.AppSettings["Domain"];

            using (TaskService ts = new TaskService(strServer, strUsername, strDomain, strPassword))
            {
                foreach (Task task in ts.RootFolder.Tasks)
                {
                    string strName = task.Name;
                }
            }

has anyone found the source of this problem or a solution?

thanks