While running a website on localhost I got this error.
Unable to make the session state request to the session state server. Please ensure that the ASP.NET State service is started and that the client and server ports are the same. If the server is on a remote machine, please ensure that it accepts remote requests by checking the value of HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\aspnet_state\Parameters\AllowRemoteConnection
If the server is on the local machine, and if the before mentioned registry value does not exist or is set to 0, then the state server connection string must use either 'localhost' or '127.0.0.1' as the server name.
This website was running sucessfully a few minutes ago. But after I restarted my PC its throwing me an error.



By default the "ASP .Net State Service" is stopped in Windows server 2003 and the startup type is manual. Please go to:
Control Panel-Administrative tools-Services then double click the Service "ASP .Net State Service" and make the startup type as Automatic then start the service.
I beleive all should be fine after that, please look at the attached images too.
Hope this helps



u have to start Asp.Net State Service.