See if a candidate is covered under the OBC category then one can't apply for the EWS certificate. But as you are a general candidate and you have no OBC certification then you can apply for the EWS certificate. Technically there should be much of a problem. Although I would recommend you to visit your BDO/SDO/DM office regarding the matter and get it discussed with the officials there, they can provide you more concrete information. Technically there shouldn't be any problem and you can apply. Although its better for you to get confirmed from a professional.

The eligibility criteria for EWS certificate is provided below:

• The annual income of the family of candidate should not exceed 8lakh per annum.
• The family should not hold 5 or more than 5 acres of land.
• The family shouldn't have a residential area more than 1000 sq feet.
• The family shouldn't have a residential plot (in notified municipalities) of an area 100 square yards or more.
• The family shouldn't have residential plot (other than in notified municipalities) of area 200 square yards or more.

I hope this answer helps. All the very best for your future endeavors!