Problem with Format method of Win32_Volume Class.

EDN Admin · Dec 15, 2008

I try to create console application which will be format every volumes in the system (of course, in the real application user will select the volume). For this task I try to use Format method of Win32_Volume Class, but pSvc->ExecMethod return 0x80041008 (Invalid parameter was specified.) for every volume. Next you can find source code of my simple console application which demonstrates this problem:



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. 
}
// Step 2: -------------------------------------------------- 
// Set general COM security levels -------------------------- 
// Note: If you are using Windows 2000, you must 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 negotiates service 
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. 
}
// 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. 
}
// Step 4: --------------------------------------------------- 
// Connect to WMI through the IWbemLocator::ConnectServer method 
IWbemServices *pSvc = NULL;
// Connect to the local rootcimv2 namespace 
// and obtain pointer pSvc to make IWbemServices calls. 
hres = pLoc->ConnectServer(
_bstr_t(L"ROOT\CIMV2"),
NULL,
NULL,
0,
NULL,
0,
0,
&pSvc 
);
if (FAILED(hres))
{
 cout << "Could not connect. Error code = 0x" << hex << hres << endl;
 pLoc->Release();
 CoUninitialize();
 return 1; // Program has failed. 
}
cout << "Connected to ROOT\CIMV2 WMI namespace" << endl;

// Step 5: -------------------------------------------------- 
// Set security levels for 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 << "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 ---- 
BSTR MethodName = SysAllocString(L"Format");
BSTR ClassName = SysAllocString(L"Win32_Volume");
IWbemClassObject* pClass = NULL;
hres = pSvc->GetObject(ClassName, 0, NULL, &pClass, NULL);
IEnumWbemClassObject* pEnumerator = NULL;
hres = pSvc->ExecQuery(
bstr_t("WQL"),
bstr_t("SELECT * FROM Win32_Volume"),
WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
NULL,
&pEnumerator);
IWbemClassObject *pclsObj;
ULONG uReturn = 0;
while (pEnumerator)
{
 HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1, &pclsObj, &uReturn);
 if(0 == uReturn)
 {
 break;
 }
 VARIANT vtProp;
 // Get the value of the Name property 
 hr = pclsObj->Get(L"DeviceID", 0, &vtProp, 0, 0);
 wcout << " DeviceID : " << vtProp.bstrVal << endl;
 IWbemClassObject* pClass = NULL;
 hres = pSvc->GetObject(ClassName, 0, NULL, &pClass, NULL);
 IWbemClassObject* pInParamsDefinition = NULL;
 hres = pClass->GetMethod(MethodName, 0, &pInParamsDefinition, NULL); 
 IWbemClassObject* pClassInstance = NULL;
 hres = pInParamsDefinition->SpawnInstance(0, &pClassInstance);
 // Create the values for the in parameters 
 VARIANT varFileSystem;
 VariantInit(&varFileSystem);
 varFileSystem.vt = VT_BSTR;
 varFileSystem.bstrVal = L"NTFS";
 VARIANT varQuickFormat;
 VariantInit(&varQuickFormat);
 varQuickFormat.vt = VT_BOOL;
 varQuickFormat.boolVal = VARIANT_TRUE; 
 VARIANT varLabel;
 VariantInit(&varLabel);
 varLabel.vt = VT_BSTR;
 varLabel.bstrVal = L"";
 VARIANT varEnableCompression;
 VariantInit(&varEnableCompression);
 varEnableCompression.vt = VT_BOOL;
 varEnableCompression.boolVal = VARIANT_FALSE;
 // Store the value for the in parameters 
 hres = pClassInstance->Put(L"FileSystem", 0, &varFileSystem, 0);
 hres = pClassInstance->Put(L"QuickFormat", 0, &varQuickFormat, 0); 
 hres = pClassInstance->Put(L"Label", 0, &varLabel, 0);
 hres = pClassInstance->Put(L"EnableCompression", 0, &varEnableCompression, 0);
 // Execute Method 
 IWbemClassObject* pOutParams = NULL; 
 
 hres = pSvc->ExecMethod(vtProp.bstrVal, MethodName, 0, NULL, pClassInstance, &pOutParams, NULL);
}


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Problem with Format method of Win32_Volume Class.

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