ASP.Net-Common occur while enabling Session State

"Session state can only be used when enableSessionState is set to true, either in a configuration file or in the Page directive. Please also make sure that System.Web.SessionStateModule or a custom session state module is included in the <configuration>\<system.web>\<httpModules> section in the application configuration.".

This error occurs if you are using Session State in your ASP.Net Pages.

Session["Name"] = "Bhupesh Sharma"; //in your c# code
The solution is you need to do these 3 things in your ASP.NET web.config:
1. locate under the <system.web> <sessionState mode = "InProc"/> ... </system.web>
2. modify the <httpModules><add name="session" type="System.Web.SessionState.SessionStateModule"/>
3. modify <pages enableSessionState="true" />