While trying to understand the program flow better during troubleshooting of a performance issue, I added a IHttpModule that was meant to log all application events.
However attaching to the MapRequestHandler caused the routing to break down, and now all calls to /modules/* was handled by the static file handler responding with a 404 causing among other things the dashboard to malfunction.
I can guess, but I rather just ask anyway; How can it be that attaching to an event should cause such a side effect?
Is there any other events in ASP.Net/EPiServer that I must not attach to without breaking built in functionality?
What's the order of your modules?
But why not activate the log4net-logging? EPi has very good logging in place in all of their code and it catches your errors without needing to implement own logging events.
It was the last module. The logging is enabled, but it doesn't log the asp.net lifecycle application events.