sessionState time out not working

I've set the sesstionstate time out to be 60 i.e. 1 hour. But, 开发者_JAVA百科users are still getting session expired messages after 20min.

we are using Windows Server 2008 to host the asp.net application. could anyone please tell me why could session expire in 20min please?

I'm using windows authentication. below is my web config:

<sessionState  timeout="60" />

Check the IIS Session amount. It can be vary from the .NET session amount.

Configure Session Time-out (IIS 7)
See also this question

By default, the session expires when the user has not requested or refreshed a page in the ASP application for 20 minutes

First Check the Windows Event Log to ensure that the Worker Process is not being forced to recycle. There may be something in your code that causes the Worker Process to force itself to recycle in which case when the session is stored inProc it will loose all session values it's holding.

You need to make these changes in the IIS=>Pool Application=>Advance Setting...