Not able to get UniqueId of CPU using WMI classes c++ - c++

Question

In an application, it needs to retrieve, a system specific UniqueId. SO that I have tried to retrive the UniqueId of the CPU. and I am using WMI class property to retrieve that.
But on trying to retrieve the 'UniqueId' property of win32_processor class, it returns VT_NULL in the variant in which the output is expected. But in the same time it is providing valid outputs for other properties like, deciveId, processorId etc. but those are not unique and can't fulfil my purpose.
Any one know why this happens? plz help me....
below is the code that i used... please have a look, and say whether there is any problem in that....
what modification can i do to make it work...
if(CoInitializeSecurity( NULL,
-1,
NULL,
NULL,
RPC_C_AUTHN_LEVEL_PKT,
RPC_C_IMP_LEVEL_IMPERSONATE,
NULL,
EOAC_NONE,
0
) != S_OK)
return;
IWbemLocator * pIWbemLocator = NULL;
IWbemServices * pWbemServices = NULL;
IEnumWbemClassObject * pEnumObject = NULL;
BSTR bstrNamespace = (L"root\\cimv2");
if(CoCreateInstance (
CLSID_WbemAdministrativeLocator,
NULL ,
CLSCTX_INPROC_SERVER | CLSCTX_LOCAL_SERVER ,
IID_IUnknown ,
( void ** ) & pIWbemLocator
) != S_OK)
return;
if(pIWbemLocator->ConnectServer(
bstrNamespace, // Namespace
NULL, // Userid
NULL, // PW
NULL, // Locale
0, // flags
NULL, // Authority
NULL, // Context
&pWbemServices
) != S_OK)
return;
HRESULT hRes;
BSTR strQuery = (L"Select * from Win32_Processor");
BSTR strQL = (L"WQL");
hRes = pWbemServices->ExecQuery(strQL, strQuery,WBEM_FLAG_RETURN_IMMEDIATELY,NULL,&pEnumObject);
if(hRes != S_OK)
{
MessageBox("Could not execute Query");
return;
}
ULONG uCount = 1, uReturned;
IWbemClassObject * pClassObject = NULL;
hRes = pEnumObject->Reset();
if(hRes != S_OK)
{
MessageBox("Could not Enumerate");
return;
}
hRes = pEnumObject->Next(WBEM_INFINITE,uCount, &pClassObject, &uReturned);
if(hRes != S_OK)
{
MessageBox("Could not Enumerate");
return;
}
VARIANT v;
BSTR strClassProp = SysAllocString(L"UniqueId");
hRes = pClassObject->Get(strClassProp, 0, &v, 0, 0);// here the v is VT_NULL but works if the vlaue of strClassProp is processerId, deviceId
if(hRes != S_OK)
{
MessageBox("Could not Get Value");
return;
}
SysFreeString(strClassProp);
_bstr_t bstrPath = &v; //it causes exception if the v is VT_NULL in other cases its working
char* strPath = new char [1024];
_stprintf(strPath, ("%s"),(char*)bstrPath);
if (SUCCEEDED(hRes))
MessageBox(strPath);
Expects expert advice and help....
Thanks in Advance....