has anybody worked in XML with C++
i have written following code and i don't know why it's not working
#include "stdafx.h"
#include "stdio.h"
#include "atlbase.h"
#import "msxml3.dll"
using namespace MSXML2;

inline void EVAL_HR( HRESULT _hr )
{ if FAILED(_hr) throw(_hr); }

int main(int argc, char* argv[])
{
USES_CONVERSION;
try
{
IXMLDOMDocumentPtr objDOMDoc;

EVAL_HR(CoInitialize(NULL));
EVAL_HR(objDOMDoc.CreateInstance("Msxml2.DOMDocument.3.0"));

_variant_t varXml("C:\\Sample.xml");
_variant_t varOut((bool)TRUE);

objDOMDoc->async = false;
varOut = objDOMDoc->load(varXml);
IXMLDOMNode *NewNode;
NewNode = objDOMDoc->createElement("Location");
objDOMDoc->documentElement->appendChild(NewKid);

and this statement appendchild gives me exception
following is my XML file


<?xmlversion ='1.0' encoding='utf-8'?>
<Sample>
<child>"remove this node"</child>
</Sample>

please help me.
it's urgent.
anu