validating an XML file against a DTD

[arielt]

Hello all!
I'm trying to validate an XML file against a DTD using Microsoft DOM in C++.
I do something like:

IXMLDOMDocumentPtr pDTDDoc = NULL;
pDTDDoc.CreateInstance(CLSID_DOMDocument);

pDoc->load("D:\A.xml"

// Add the DTD header
_bstr_t TheXmlString = &quot;<!DOCTYPE RuleSet SYSTEM 'D:\\Dtd\\RuleSet.dtd'>&quot;
+ pDoc->GetfirstChild()->Getxml();

// Validate
pDTDLoadedDoc->PutresolveExternals(true);
pDTDLoadedDoc->PutvalidateOnParse(true);
pDTDLoadedDoc->loadXML(TheXmlString);

_bstr_t Error = pDTDLoadedDoc->GetparseError()->GeterrorCode();

And the error is allways 0, even when the XML does not follows the DTD rules.
Someone knows why and what to do?

Thanks