Maintain Session

Question

Hi
I've done my website for conduncting online examination it's working fine in my lan network but on webserver when I'm hosting it at the time of examination if two student are login and giving the examination at that time if student 1 has given answer of some question then eg student1 solved que no. 3 and at same time if student 2 is solving the same question set he will be displayed que no 4 not from que no 1. Why this is happening while I'm maintaining sessionstate inproc only. It mean it is sharing the data in different user why it is happening?
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