Losing Session State with ASP.NET/SQL Server

Question

I have a ASP.NET MVC workflow configured as two websites managed by a load balancer. The websites use Sql Server as the session state provider and have authentication switch

Answer 1

1. Using IIS Manager, double-check your machine key settings at both the root and website levels.

2. Review the IsolateApps modifier on the machine key element - http://msdn.microsoft.com/en-us/library/w8h3skw9%28v=vs.100%29.aspx

3. Did you recently upgrade from 3.5 to 4.0?

4. Last resort - recycle the appPools on both machines, and restart IIS.