Do not wanna enter a person on another person's session

hi guys
i have a problem about sessions. I have student user type on the system. After a user logined the system the adress bar will be like that http://localhost:49216/deneme1/student.aspx if another person who did not login the system , will write the adress bar http://localhost:49216/deneme1/student.aspx he/she can enter the system like the last logined person.


how can i fixed it?


thanks..

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