Error 6 Deleting Files with ShFileOperation()

Hi Guys,

I'm getting and error code 6 (which I think is an invalid handle) when
deleting files.  It is happening about half the time.

function DeleteAllFilesWithMask(sFile : String) : Boolean;
var
  Info: TSHFileOpStruct;
  lAborted : Bool;
begin
  lAborted := False;
  with Info do
  begin
    Wnd := Application.Handle;
    wFunc := FO_DELETE;
    pFrom := pChar(sFile);
    pTo := pChar('');
    fFlags := FOF_FILESONLY or FOF_ALLOWUNDO or FOF_NOCONFIRMATION or
FOF_SILENT;
    fAnyOperationsAborted := lAborted;
    hNameMappings := nil;
    lpszProgressTitle := nil;
  end;
  try
      Result := (SHFileOperation(Info) = 0);
  finally
    if lAborted then
      Result := False;
  end;
end;

Is it possible for Application.Handle to provide an invalid handle? If
so, what can I use?

Thanks,
Steve