SessionID changes after each post back or each refresh of page.
if you have problem of changing sessionID (Session.SessionID) on each post back or refresh.
you can add Global.asax file In your Application.
Once i Got this problem.i dont know why this happning. But i found Solution
by help of my friend.
you can Add Global.asax in your application folder
You can Declare dummy session in Your Page Load event handler.
if you find and other solution or reason for this problem please leave