title: Calling next at IEnumWbemClassObject hangs the app
body: <p>I have a simple function that gets the harddisk serial number using WMI, but the following call will hang the app like if it entered an infinite loop:</p>
  
  <pre><code>HRESULT hr = pEnumerator-&gt;Next(WBEM_INFINITE, 1, &amp;pclsObj, &amp;uReturn);
  </code></pre>
  
  <p>The full code is:</p>
  
  <pre><code>std::string GetHarddiskSerialNumber()
  {
          HRESULT hres;
  
          // No need to initialize COM in openFL, as it seems that its already initialized when starting windows
          // Step 1: --------------------------------------------------
          // Initialize COM. ------------------------------------------
  
          hres =  CoInitializeEx(0, COINIT_MULTITHREADED); 
          if (FAILED(hres))
          {
              cout &lt;&lt; "Failed to initialize COM library. Error code = 0x" 
                  &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              return "Failed to initialize COM library. Error code = 0x";                  // Program has failed.
          }
  
          // Step 2: --------------------------------------------------
          // Set general COM security levels --------------------------
          // Note: If you are using Windows 2000, you need to specify -
          // the default authentication credentials for a user by using
          // a SOLE_AUTHENTICATION_LIST structure in the pAuthList ----
          // parameter of CoInitializeSecurity ------------------------
          hres =  CoInitializeSecurity(
              NULL, 
              -1,                          // COM authentication
              NULL,                        // Authentication services
              NULL,                        // Reserved
              RPC_C_AUTHN_LEVEL_DEFAULT,   // Default authentication 
              RPC_C_IMP_LEVEL_IMPERSONATE, // Default Impersonation  
              NULL,                        // Authentication info
              EOAC_NONE,                   // Additional capabilities 
              NULL                         // Reserved
              );
  
  
          if (FAILED(hres))
          {
              cout &lt;&lt; "Failed to initialize security. Error code = 0x" 
                  &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              CoUninitialize();
              return "Failed to initialize security. Error code = 0x";                    // Program has failed.
          }
  
          // Step 3: ---------------------------------------------------
          // Obtain the initial locator to WMI -------------------------
  
  
          IWbemLocator *pLoc = NULL;
  
          hres = CoCreateInstance(
              CLSID_WbemLocator,             
              0, 
              CLSCTX_INPROC_SERVER, 
              IID_IWbemLocator, (LPVOID *) &amp;pLoc);
  
          if (FAILED(hres))
          {
              cout &lt;&lt; "Failed to create IWbemLocator object."
                  &lt;&lt; " Err code = 0x"
                  &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              CoUninitialize();
              return "1";                 // Program has failed.
          }
  
          // Step 4: -----------------------------------------------------
          // Connect to WMI through the IWbemLocator::ConnectServer method
  
          IWbemServices *pSvc = NULL;
  
          // Connect to the root\cimv2 namespace with
          // the current user and obtain pointer pSvc
          // to make IWbemServices calls.
          hres = pLoc-&gt;ConnectServer(
               _bstr_t(L"ROOT\\CIMV2"), // Object path of WMI namespace
               NULL,                    // User name. NULL = current user
               NULL,                    // User password. NULL = current
               0,                       // Locale. NULL indicates current
               NULL,                    // Security flags.
               0,                       // Authority (for example, Kerberos)
               0,                       // Context object 
               &amp;pSvc                    // pointer to IWbemServices proxy
               );
  
          if (FAILED(hres))
          {
              cout &lt;&lt; "Could not connect. Error code = 0x" 
                   &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              pLoc-&gt;Release();     
              CoUninitialize();
              return "1";                // Program has failed.
          }
  
          //cout &lt;&lt; "Connected to ROOT\\CIMV2 WMI namespace" &lt;&lt; endl;
  
  
          // Step 5: --------------------------------------------------
          // Set security levels on the proxy -------------------------
  
          hres = CoSetProxyBlanket(
             pSvc,                        // Indicates the proxy to set
             RPC_C_AUTHN_WINNT,           // RPC_C_AUTHN_xxx
             RPC_C_AUTHZ_NONE,            // RPC_C_AUTHZ_xxx
             NULL,                        // Server principal name 
             RPC_C_AUTHN_LEVEL_CALL,      // RPC_C_AUTHN_LEVEL_xxx 
             RPC_C_IMP_LEVEL_IMPERSONATE, // RPC_C_IMP_LEVEL_xxx
             NULL,                        // client identity
             EOAC_NONE                    // proxy capabilities 
          );
  
          if (FAILED(hres))
          {
              cout &lt;&lt; "Could not set proxy blanket. Error code = 0x" 
                  &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              pSvc-&gt;Release();
              pLoc-&gt;Release();     
              CoUninitialize();
              return "1";               // Program has failed.
          }
  
          // Step 6: --------------------------------------------------
          // Use the IWbemServices pointer to make requests of WMI ----
  
          // For example, get the name of the operating system
          IEnumWbemClassObject* pEnumerator = NULL;
          hres = pSvc-&gt;ExecQuery(
              bstr_t("WQL"), 
              bstr_t("SELECT * FROM Win32_OperatingSystem"),
              WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY, 
              NULL,
              &amp;pEnumerator);
  
          if (FAILED(hres))
          {
              cout &lt;&lt; "Query for operating system name failed."
                  &lt;&lt; " Error code = 0x" 
                  &lt;&lt; hex &lt;&lt; hres &lt;&lt; endl;
              pSvc-&gt;Release();
              pLoc-&gt;Release();
              CoUninitialize();
              return "1";               // Program has failed.
          }
  
          // Step 7: -------------------------------------------------
          // Get the data from the query in step 6 -------------------
  
          IWbemClassObject *pclsObj;
          ULONG uReturn = 0;
          std::string result= "";
          while (pEnumerator)
          {
              // this call will hang the app:
              HRESULT hr = pEnumerator-&gt;Next(WBEM_INFINITE, 1, &amp;pclsObj, &amp;uReturn);
  
  
              if(0 == uReturn)
              {
                  break;
              }
  
              VARIANT vtProp;
  
              // Get the value of the Name property
              hr = pclsObj-&gt;Get(L"SerialNumber", 0, &amp;vtProp, 0, 0);
              wstring ws(vtProp.bstrVal, SysStringLen(vtProp.bstrVal));
              result = string(ws.begin(), ws.end());
              VariantClear(&amp;vtProp);
  
              hr = pclsObj-&gt;Get(L"Manufacturer", 0, &amp;vtProp, 0, 0);
              wstring ws2(vtProp.bstrVal, SysStringLen(vtProp.bstrVal));
              result+=",";
              result+= string(ws2.begin(), ws2.end());
              VariantClear(&amp;vtProp);
  
  
  
  
  
              pclsObj-&gt;Release();
          }
  
          // Cleanup
          // ========
  
          pSvc-&gt;Release();
          pLoc-&gt;Release();
          pEnumerator-&gt;Release();
          //pclsObj-&gt;Release();
          CoUninitialize();
          return result;
  
      }
  }// name space
  </code></pre>
  
  <p>Any idea?</p>