97[Notice deemed to be valid in certain circumstances.
42. Where an assessee has appeared in any
proceeding or cooperated in any inquiry relating to an assessment or
reassessment, it shall be deemed that any notice under any provision of this
Act, which is required to be served upon him, has been duly served upon him in
time in accordance with the provisions of this Act and such assessee shall be
precluded from taking any objection in any proceeding or inquiry under this Act
that the notice was—
(a) not served upon him; or
(b) not served upon him in time; or
(c) served upon him in an improper manner:
Provided that
nothing contained in this section shall apply where
the assessee has raised such objection before the completion of such
assessment or reassessment.]