How many times can i appear for exam.

I have taken admission in a good Law college during 2015. I could not appear for 2015-16 ( Nov 15, Apr 16) exams though I submitted exam forms (Sem 1). In the year i.e. 2016 (Nov 16), I am not be able to appear for exams due to some of my personal reasons. Can start appearing for Sem 1 exams from Apr 2017 or Nov 2017 exams or the University or college will cancel my admission. How many times or years my the admission shall be in effect or valid ? I heard that you can try as many times as you can? Regards