Hidden form shows automatically?

Hi,

I use a form which is created unvisible and has the ExStyle set:

  Params.ExStyle := Params.ExStyle or WS_EX_NOACTIVATE;

So far OK, but when I loop about it's components by

  for i := 0 to HiddenForm.ComponentCount - 1 do
  begin
     .....
     if HiddenForm.Components[i] is T........ then {....};
  end;

it becomes for a short time visible. How can I block this?

Thanks,
John