04 February 2014
CA Final registration is valid for 5 years from the date of registration. Thus your final registration shall expires on 26-3-2014.
As per the ICAI regulations to appear and write CA exams the registration for the concern course is should be valid and in force as on the date of writing of exams. So for May 2014 exams your registration is not in force and valid,
So you required to get renewal(revalidate) your CA Final registration for appearing in May 2014 CA Final exams.