Server.Transfer does not run ASP.NET pipeline
Things I’ve learnt today: One.
What I’ve learnt: If you use the convenient (if old school) Server.Transfer method to render a different page to a client then you need to be aware that ASP.NET pipeline events1 will not run. You know - BeginRequest, AuthenticateRequest - unimportant things like that.
Basically - nothing that happens in Global.asax, [...]