德尔福中的OLE错误805303E？

   procédure TCustomGeckoBrowser.LoadHTML (htmlCode: string);
 var
   domwindow: nsIDOMWindow;
    domdoc: nsIDOMDocument;
    domhtmldoc: nsIDOMHTMLDocument;
    nsstr: IInterfacedString;
begin
  domwindow: = GetContentWindow;
  domdoc: = GetContentDocument;
  domhtmldoc: = domdoc que nsIDOMHTMLDocument;

  nsstr: = nouvelleChaine;
  nsstr.Assign (htmlCode);
  domhtmldoc.Write (nsstr.AString);
end;

domhtmldoc.Write (nsstr.AString)

    nsIDOMHTMLDocument = interface(nsIDOMDocument)
      procedure Writeln(const text: nsAString); safecall;
    .....
    end;