>>423
そうですね、ソースのその部分を載せてみます

VOID XmlTest() {
  MSXML4::IXMLDOMDocument* w_lpDocument;
  MSXML4::IXMLDOMElement* w_lpRoot;
  MSXML4::IXMLDOMNode* w_lpNode;
  TCHAR w_szAppPath[MAX_PATH];
  std::wstring w_strAppPath;
  std::wstring w_strXmlFile;
  _variant_t w_varText(_TEXT("ChangeTestText"));

  ::GetModuleFileName(NULL, w_szAppPath, MAX_PATH);
  w_strAppPath = w_szAppPath;
  w_strXmlFile = w_strAppPath.substr(0, (w_strAppPath.rfind(_TEXT('\\')) + 1));
  w_strXmlFile += _TEXT("Test.xml");

  ::CoInitialize(NULL);

  if (SUCCEEDED(CoCreateInstance(MSXML4::CLSID_DOMDocument, NULL, CLSCTX_INPROC_SERVER,
      MSXML4::IID_IXMLDOMDocument, (LPVOID*)(&w_lpDocument)))) {
    w_lpDocument->async = VARIANT_FALSE;
    if(w_lpDocument->load(_variant_t(_TEXT("XMLファイルのパス"))) == VARIANT_TRUE) {
      w_lpRoot = w_lpDocument->documentElement;
      w_lpNode = w_lpRoot->firstChild;  ←※ここでエラー
      w_lpNode->nodeValue = w_varText.GetVARIANT();
      w_lpDocument->save(_variant_t(w_strXmlFile.c_str()));
    }
    w_lpDocument->Release();
  }
  ::CoUninitialize();
}