session destroying automatically, what may be the reason?

I am facing very weird problem, i made an web application for my client, he is from usa, I deployed application to "xyz.co.uk", at my local system, the project function proper. But what is happening that at ma开发者_JAVA百科in server the session is destroying automatically, before the idle time. I have been figuring out this problem for long but could not solved it. Please list me out what may be the reason behind this session out. I am using in process session.

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If your IIS is set to use a web farm (i.e. more than one process) then you may find your requests are being diverted to different processes, and the session data isn't being copied across. To solve this, you change it back to one process, or use a session state server process on the machine.

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ASP.NET Session Timeouts too early

Also, check if Keep-Alive feature is enabled in IIS and application pool is not being recycled on a regular manner.