在wince下不能解析xml，不能加载

::CoInitialize(NULL);
{
MSXML2::IXMLDOMDocument2Ptr pMyDoc=NULL;
pMyDoc.CreateInstance(__uuidof(MSXML2::DOMDocument));//

if(S_OK!=pMyDoc->load(TEXT("temp.txt")))
goto RETURN_FALSE;
if(pMyDoc==NULL)
goto RETURN_FALSE;
MSXML2::IXMLDOMNodeListPtr pNodeList=NULL;
MSXML2::IXMLDOMNodePtr pNodes=NULL;
pNodes=pMyDoc->selectSingleNode("ArrayOfString");
if(NULL==pNodes) goto RETURN_FALSE;
pNodeList=pNodes->childNodes;
if(NULL==pNodeList) goto RETURN_FALSE;
MSXML2::IXMLDOMNodePtr pNode=NULL;
for(int i=0;i <pNodeList->length;++i)
{
pNode=pNodeList->nextNode();
comboProvince.AddString(pNode->Gettext());
}
pMyDoc.Release();
}
RETURN_FALSE:
::CoUninitialize();
return false;
RETURN_TRUE:
::CoUninitialize();
return true;

执行到selectSingleNode之后返回的是NULL,我该怎么得到错误消息呢？？

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我把代码改成这样了还是不行，加载失败，高手帮帮忙吧
HRESULT hr;
CComPtr <IXMLDOMDocument> m_iXMLDoc;
CComPtr <IXMLDOMElement> iRooterElm=NULL;
if(FAILED( m_iXMLDoc.CoCreateInstance( __uuidof( DOMDocument )))) goto RETURN_FALSE;
VARIANT_BOOL bSuccess=false;
m_iXMLDoc->put_async(FALSE);
m_iXMLDoc->put_resolveExternals(VARIANT_FALSE