Sessions randomly clear on Win2008 ASP.NET website

I couldn't find anything about this online so I thought I'd ask here. Do any of you have issues with sessions just randomly clearing on a Windows 2008 Server environment? This problem is completely random and very unpredictable. I have no code that clears sessions except on logout, and not quite sure what could be causing it (well, I have ideas...)

My host, who I've been with for many years (and never had a problem with) is telling me that Windows 2003 is better at managing session variables and that I will likely be rid of this session clearing issue if I were to move to a 2003 Server environment. Thing is, I'm already set up and running on IIS 7 with the URL Rewrite module and I'd rather not move or reconfigure URL rewriting. Tech support says the App Pool I am running on is configured properly. My session timeout is set to 60 minutes in Web.config and my host tells me that session timeout is set to 60 minutes for my domain.

I could optionally go with an Azure AppFabric Cache for sessions but I'd rather not pay an extra $50 a month--it's a pretty small and low income site. I'm currently using a SQL Azure database but from what I hear, database sessions are not开发者_开发问答 ideal on SQL Azure.

Thoughts?

Are you modifying any files in the web site?

Changes to the folder or file structure of the web site often triggers an app pool recycling, resetting sessions. The work-around is to use a durable session store like the SQL Server Session State provider.

Most likely answer is your app pool is recycling on you for some reason or another which will dump your in process session every time. Proximate causes can be lots of things, especially if app pools are shared. An easy way to see if your app pool is getting dumped is to take advantage of asp.net heartbeat monitoring, it could be configured to email you when these events occur.