Error 0x8004100e connecting to WMI namespace - c++

Question

I'm using Windows 7 and now I want to develop a program with WMI.
I've read MSDN and found this example code.
#include "stdafx.h"
#define _WIN32_DCOM
#include <iostream>
using namespace std;
#include <comdef.h>
#include <Wbemidl.h>
#include <conio.h>
# pragma comment(lib, "wbemuuid.lib")
BOOL ManageWMI();
int main(int argc, char* argv[])
{
if(ManageWMI()) printf("%WMI Error!");
_getch();
return 0;
}
BOOL ManageWMI()
{
HRESULT hres;
// Step 1: --------------------------------------------------
// Initialize COM. ------------------------------------------
hres = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hres))
{
cout << "Failed to initialize COM library. Error code = 0x"
<< hex << hres << endl;
return 1; // Program has failed.
}
cout << "step 1" << endl;
// 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 << "Failed to initialize security. Error code = 0x"
<< hex << hres << endl;
CoUninitialize();
return 1; // Program has failed.
}
cout << "step 2 " << endl;
// Step 3: ---------------------------------------------------
// Obtain the initial locator to WMI -------------------------
IWbemLocator *pLoc = NULL;
hres = CoCreateInstance(
CLSID_WbemLocator,
0,
CLSCTX_INPROC_SERVER,
IID_IWbemLocator, (LPVOID *) &pLoc);
if (FAILED(hres))
{
cout << "Failed to create IWbemLocator object."
<< " Err code = 0x"
<< hex << hres << endl;
CoUninitialize();
return 1; // Program has failed.
}
cout << "step 3" << endl;
// 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->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 (e.g. Kerberos)
0, // Context object
&pSvc // pointer to IWbemServices proxy
);
if (FAILED(hres))
{
cout << "Could not connect. Error code = 0x"
<< hex << hres << endl;
pLoc->Release();
cout << "released!!" << endl;
CoUninitialize();
cout << "counitialized !!" << endl;
return 1; // Program has failed.
}
cout<< "step 4" << endl;
cout << "Connected to ROOT//CIMV2 WMI namespace" << 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
);
cout << "step 5" << endl;
if (FAILED(hres))
{
cout << "Could not set proxy blanket. Error code = 0x"
<< hex << hres << endl;
pSvc->Release();
pLoc->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->ExecQuery(
bstr_t("WQL"),
bstr_t("SELECT * FROM Win32_NetworkAdapterConfiguration WHERE IPEnabled = ''TRUE''"),
WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
NULL,
&pEnumerator);
if (FAILED(hres))
{
cout << "Query for Network Adapter Configuration failed."
<< " Error code = 0x"
<< hex << hres << endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
return 1; // Program has failed.
}
// Step 7: -------------------------------------------------
// Get the data from the query in step 6 -------------------
IWbemClassObject *pclsObj;
ULONG uReturn = 0;
while (pEnumerator)
{
HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1,
&pclsObj, &uReturn);
if(0 == uReturn)
{
break;
}
VARIANT vtProp;
VariantInit(&vtProp);
//hr = pclsObj->Get(L"IPSubnet", 0, &vtProp, 0, 0);
// Get the value of the Enable property
hr = pclsObj->Get(L"IPEnabled", 0, &vtProp, 0, 0);
// Get the value of the MacAddress property
if(vtProp.boolVal)
{
hr = pclsObj->Get(L"MacAddress", 0, &vtProp, 0, 0);
wcout << " MacAddress : " << vtProp.bstrVal << endl;
}
hr = pclsObj->Get(L"IPEnabled", 0, &vtProp, 0, 0);
if(vtProp.boolVal)
{
LONG lstart, lend;
LONG idx = -1;
BSTR* pbstr;
SAFEARRAY *sa;
hr = pclsObj->Get(L"Description", 0, &vtProp, 0, 0);
if(!FAILED(hr))
{
wcout << "Description: " << vtProp.bstrVal << endl;
}
hr = pclsObj->Get(L"DNSHostName", 0, &vtProp, 0, 0);
if(!FAILED(hr))
{
cout << "DNS:" << vtProp.bstrVal << endl;
}
hr = pclsObj->Get(L"IPAddress", 0, &vtProp, 0, 0);
if(!FAILED(hr))
{
SAFEARRAY *psa = vtProp.parray;
cout << "IP Address::" << psa << endl;
}
}
VariantClear(&vtProp);
}
// Cleanup
// ========
pSvc->Release();
pLoc->Release();
pEnumerator->Release();
pclsObj->Release();
CoUninitialize();
return 0; // Program successfully completed.
}
However, these code doesn't work on my computer.
It failed in "step4" with error code 0x8004100e.
I googled and restart my WMI service but doesn't work either.
Does anyone had the same experience and solved that? Hope you give me some help. Thanks...

Answer 1

You are using a wrong syntax for the ROOT//CIMV2 namespace try changing to ROOT\\CIMV2
hres = pLoc->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 (e.g. Kerberos)
0, // Context object
&pSvc // pointer to IWbemServices proxy
);
Btw the 0x8004100E value is the code for the WBEM_E_INVALID_NAMESPACE (Namespace specified cannot be found.) error.