RPC服务器不可用的问题

Question

  private void getServices()
        {
            ManagementObjectCollection queryCollection;
            
            string[] lvData = new string[4];
            try
            {
                queryCollection = getServiceCollection("SELECT * FROM Win32_Service","192.168.1.3","administrator","");
                foreach (ManagementObject mo in queryCollection)
                {
                    //create child node for operating system
                    //lvData[0] = mo["Name"].ToString();
                    //lvData[1] = mo["StartMode"].ToString();
                    //if (mo["Started"].Equals(true))
                    //    lvData[2] = "Started";
                    //else
                    //    lvData[2] = "Stop";
                    //lvData[3] = mo["StartName"].ToString();
                    ////create list item
                    //ListViewItem lvItem = new ListViewItem(lvData, 0);
                    //listViewServices.Items.Add(lvItem);
                    comboBox1.Items.Add(mo["Name"].ToString());
                    comboBox2.Items.Add(mo["StartName"].ToString());
               }
            }
            catch (Exception e)
            {
                MessageBox.Show("Error: " + e);
            }
      }
        ///   <summary> 
        ///   Get   computer   service   collection 
        ///   </summary> 
        ///   <param   name= "stringQuery "> </param> 
        ///   <returns> queryCollection </returns> 
        private ManagementObjectCollection getServiceCollection(string stringQuery,string ip,string userName,string pws)
        {
            ManagementObjectSearcher query;
            ManagementObjectCollection queryCollection = null;
            System.Management.ObjectQuery oq;
            string stringMachineName = " ";            ConnectionOptions co = new ConnectionOptions();
            System.Management.ManagementScope ms = new System.Management.ManagementScope("\\\\ " + ip+ "\\root\\cimv2",co);
           
            //Status 
            //updateStatus("Getting   Services   Information ");            //Query   remote   computer   across   the   connection 
                        try
            {
                ms.Connect();
                oq = new System.Management.ObjectQuery(stringQuery);
                query = new ManagementObjectSearcher(ms, oq);
                queryCollection = query.Get();
            }
            catch (Exception e1)
            {
                MessageBox.Show("Error:   " + e1);
            }
            //Status 
            //updateStatus("Ready ");
            //this.Update();            return queryCollection;        }     }
   我已经启动了RPC，和 RPC locator 服务，并且关闭了，系统防火墙和360软件，但是仍然报RPC服务器不可以用，IP地址是我本机的Ip，请高手帮忙指点下