You should not experiment any timeout while posting a thread...
1 Can you explain better what is happening?
2 Are you loosing session within a couple of minutes?
3 Are you hosting the website using a shred Web Hosting provider or a dev machine?
On ASP.NET, you can configure the session using the
sessionState element within the web.config. By default, the timeout value is set by 20 mins
(The most common reason on loosing session on ASP.NET is the aplication pool being recycled, not the session timeout)