Cannot bind to the target method because its signature or security transparency is not compatible with that of the delegate type.

I have a problem with my MVC application. I am using a performance monitor tool (stackify). I am getting weired errors on several ajax methods in the erros log on regular basis.

Cannot bind to the target method because its signature or security transparency is not compatible with that of the delegate type.

System.ArgumentException: Cannot bind to the target method because its signature or security transparency is not compatible with that of the delegate type. at System.Delegate.CreateDelegate at System.Web.HttpApplication.HookupEventHandlersForApplicationAndModules

But, i am not using delegate anywhere. so i have no clue. why i am getting this