Error 1503 on lunching windows service

@PaulDAndrea, sorry my ignorance. I still don't understand. I have an application in the service. Originally the code was

protected override void OnStart(string[] args)
{
      IvrApplication.Start();
}

// And for the Ivrpplication, we have 
public class IvrApplication
{
   private static object s_SyncVar = new object();
        public static object SyncVar
        {
            get { return IvrApplication.s_SyncVar; }
        }

        private static Log s_Log;
        public static Log Log
        {
            get { return s_Log; }
        }

        private static State s_State;

        public static State State
        {
            get { return s_State; }
        }

        private static Thread s_MainCodeThread;

        public static Thread MainCodeThread
        {
            get { return s_MainCodeThread; }
        }

        private static AutoResetEvent s_ThreadEvent = new AutoResetEvent(false);

        public static AutoResetEvent ThreadEvent
        {
            get { return s_ThreadEvent; }
        }

        private static string s_WorkingFolder = null;

        public static string WorkingFolder
        {
            get { return s_WorkingFolder; }
        }



        static IvrApplication()
        {
            // Constructor
            s_Log = new Log("IvrApplication.Log");
            Log.Write("IvrApplication Constructor Complete");
            AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);

        }

        static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
        {
            if (e.ExceptionObject is Exception)
            {
                Log.WriteException((Exception)e.ExceptionObject, "Domain Level Unhandled Exception");
            }
            else
            {
                Log.Write("Domain Level Unhandled Exception - No Exception Object");
            }
        }

        public static void Start()
        {

            lock (SyncVar)
            {
                if (State == State.Stopped)
                {
                    s_State = State.Starting;
                    ThreadStart ts = new ThreadStart(MainCode);
                    s_MainCodeThread = new Thread(ts);
                    s_MainCodeThread.Name = "IvrApplication";
                    s_MainCodeThread.Start();
                    Log.Write("IvrApplication Starting...");
                }

If we cannot put

IvrApplication.Start();

inside OnStart(), where is the place to go? Need code help.