Dear viewer's in this tutorial I will explain how to increase session time in ASP.Net C#. Generally we store username and password in session to move one page to otherpages. If we do not set session time suddenly Logout can be happened after 20 minutes because By default websites session timeout is 20 mines but we can increase our session time three different ways. In this situation I will show increaseing session time using web web.config.we need to change the timeout attribute for Session-state in the web.config file.