0x80020009 OLE Exception accessing any number other than 0 - c++

Question

So I'm using COM to access a third party program, I use the following Method to acquire property from server:
HRESULT ConnectToHYSYS::OLEMethod(int nType, VARIANT * pvResult, IDispatch * pDisp, LPOLESTR ptName, int cArgs...){
if (!pDisp) return E_FAIL;
va_list marker;
va_start(marker, cArgs);
DISPPARAMS dp = { NULL, NULL, 0, 0 };
DISPID dispidNamed = DISPID_PROPERTYPUT;
DISPID dispID;
char szName[200];
// Convert down to ANSI
WideCharToMultiByte(CP_ACP, 0, ptName, -1, szName, 256, NULL, NULL);
// Get DISPID for name passed...
HRESULT hr = pDisp->GetIDsOfNames(IID_NULL, &ptName, 1, LOCALE_USER_DEFAULT, &dispID);
if (FAILED(hr)) {
return hr;
}
// Allocate memory for arguments...
VARIANT * pArgs = new VARIANT[cArgs + 1];
// Extract arguments...
for (int i = 0; i < cArgs; i++) {
pArgs[i] = va_arg(marker, VARIANT);
}
// Build DISPPARAMS
dp.cArgs = cArgs;
dp.rgvarg = pArgs;
// Handle special-case for property-puts!
if (nType & DISPATCH_PROPERTYPUT) {
dp.cNamedArgs = 1;
dp.rgdispidNamedArgs = &dispidNamed;
}
// Make the call!
hr = pDisp->Invoke(dispID, IID_NULL, LOCALE_SYSTEM_DEFAULT, nType, &dp, pvResult, NULL, NULL);
if (FAILED(hr)) {
return hr;
}
// End variable-argument section...
va_end(marker);
delete[] pArgs;
return hr;
}
When I try to access an object in Collection through the following Method:
void ConnectToHYSYS::GetMaterialStream(int index) {
HRESULT hr;
VARIANT result;
VariantInit(&result);
hr = OLEMethod(DISPATCH_PROPERTYGET, &result, hyStreams, L"Item", 1, index);
CheckForHr(hr);
hyStream = result.pdispVal;}
It returns the hyStream member only if index=0; I checked the following:
1- hyStreams (the collection) pointer is not NULL
2- The member with index Im trying to access exists (The collection has 36 hyStreams but fails to get any hyStream with index more than 0)
3- When Debugging, the error happens when I make the Call
hr = pDisp->Invoke(dispID, IID_NULL, LOCALE_SYSTEM_DEFAULT, nType, &dp, pvResult, NULL, NULL);
Where hr returns above mentioned error...
Can you figure out where is the problem?
Thank you

Answer 1

The problem was in the type that was passed (index type), I think all kinds of types going through COM has to b kind of object.. anyways, changing it to _variant_t and including (without it, u get nasty errors of linking and stuff), the problem was solved and I could loop through the whole collection.