I'm trying to use a 3rd party web part in one of my pages. I can add it, but once I configure it I get an error in the ULS about a serialization exception:
"System.Runtime.Serialization.SerializationException: Type '[TheirType]' in Assembly '[TheirAssembly]' is not marked as serializable." at System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type) at System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context) at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo() at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter) at System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header inHeaders, __BinaryWriter serWriter, Boolean fCheck) at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header headers, Boolean fCheck) at System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer)
The vendor says that the web part's state doesn't serialize and so I need to use InProc session state. This is fine with me, and I made the appropriate change in the web.config file. But I still get this error. I've checked the machine.config and looked for any other web.config files that might apply but I've come up empty.
Is there anything that might be overriding the session state setting in the web.config file? Is there any other reason for SP to try to serialize session state?