Hi! I have applied for JMET and checked general category as I don't have OBC certificate at the time of applying. Now I received the certificate. Can I change it to OBC before exam and how to do it?

No its not possible afterwards.

Hi, As this a very specific query which can only be answered by the concerned people who are conducting JMET i.e. IITs. For last few years its been conducted through IIT Kanpur. Although it would be difficult to change the category once you have submitted your application but, I would still suggest