Change behavior of TXMLDocument.SaveToFile - delphi

Question

In production we sometimes have Exception of type "Access denied".
The call stack is from this line
vXML.SaveToFile(Filename);
where vXML is IXMLDocument.
Problem here is that Filename is not logged.
I tried this small testprogram.
implementation
uses
xmldoc, Unit12;
{$R *.dfm}
procedure TForm11.FormShow(Sender: TObject);
const
cnFile = 'C:\Program Files (x86)\test.xml';
var
vXML: TAttracsXMLDoc;
begin
vXML := TAttracsXMLDoc.Create(nil);
try
vXML.Active := True;
// Process vXML
vXML.SaveToFile(cnFile);
finally
vXML.Free;
end;
end;
And other unit
unit Unit12;
interface
uses
xmldoc,
xml.xmldom,
Xml.XMLIntf;
type
TAttracsXMLDoc = class(TXMLDocument)
procedure SaveToFile(const AFileName: DOMString); override;
end;
implementation
uses
Sysutils;
procedure TAttracsXMLDoc.SaveToFile(const AFileName: DOMString);
begin
try
inherited SaveToFile(AFileName);
except
on E: Exception do
begin
E.Message := E.Message + ' ' + AFileName + ' cannot be saved';
raise;
end;
end;
end;
end.
It works as intended. But problem is that interface IXMLDocument is not used anymore. I want to use code like this:
procedure TForm11.FormShow(Sender: TObject);
const
cnFile = 'C:\Program Files (x86)\test.xml';
var
vXML: IXMLDocument;
begin
vXML := NewXMLDocument;
// Process vXML
vXML.SaveToFile(cnFile);
end;
And with minimum changes on existing code catch exception above with a clear error of reason. What is the best path ?

Answer 1

Simply replace NewXMLDocument() with TAttracsXMLDoc, then you will get the behavior you want:
function NewAttracsXMLDocument: IXMLDocument;
begin
Result := TAttracsXMLDoc.Create(nil);
end;
procedure TForm11.FormShow(Sender: TObject);
const
cnFile = 'C:\Program Files (x86)\test.xml';
var
vXML: IXMLDocument;
begin
vXML := NewAttracsXMLDocument; //NewXMLDocument;
// Process vXML
vXML.SaveToFile(cnFile);
end;