We recently started having a random problem with asp.net membership throwing config errors randomly. The only change that was made in the last month was updating the servers to use .net 3.5 SP1. Here is part of the stack trace from the error that gets emailed to us when something happens on the system.
System.Configuration.ConfigurationErrorsException: An error occurred creating the configuration section handler for system.web/membership: The type initializer for 'System.Web.Configuration.MembershipSection' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Web.Configuration.MembershipSection' threw an exceptio ...
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