1) you should not rely upon false medical certifcates for taking leave .

2) you are not suffering from any illness and hence not entitled to medical leave .

3) if you are caught department will take strict disciplinary action against you

1. If you have availed medical leave based on Doctor's advise and if it is sanctioned by competent authority in your department, then you need not worry.

2. It will be valid if you take the stand that really you are sick to attend the office daily for more than 8 hours, but the exam will be of 3 hrs duration and you can manage to attend the examination inspite of your ill health, in the interest of your career..

you can carry on your preparation during medical leave but you must join your job before some days of examination. during medical leave you can't appear in examination because if you are unfit for resume your work then how can you appear in the exam. such a long duration of medical leave may be granted for any critical illness and I think it would be tough for you to get fitness certificates after 2 years without suffering from from any critical illness.

1. Unless your leave application is sanctioned you cannot proceed on leave even for preparation of your exam. If you proceed on an unauthorized leave then disciplinary proceedings will be initiated against you.

2. When you are confronted with circumstances of this nature you have to rely on your skills of persuasion to impress upon the sanctioning authority to allow you to write your exam. If nothing works then you move to court.

If you are taking medical leave on the grounds of illness, then it is advisable not to appear in exams during the leaves however if the leave is approved otherwise then on medical grounds, it would be of no hassle. If the department finds out then disciplinary action can be taken against you.

1. Your examination will be valid,

2. However, you may be charge sheeted for giving false statement about your ailment and your leave for the period when you sat for the examination, may be cancelled and you may become LWA ( leave without pay).

contact your human resources department regarding the same, the policies are different.

Legally it is not valid as medical leaves has to be supported by a medical certificate and in case of inquiry not only you but the doctor who has issued such certificate may face problems. Better go for LWP.