CLR v4.0/v4.5 can generate ETW CLR events. There is special section and for operations relating to loading and unloading application domains, assemblies, and modules. This article contains a lot of identifiers such as AppDomainID, AssemblyID, ModuleID. Descriptions of them sometimes contains word "unique". This word is parasite. All identifiers are unique, but unique only during object life. It means that it possible to have two and more different objects with the same identifier, but in different moments of an application life.