ASP.NET ships with two built-in mechanisms for doing logging and troubleshooting. Chasing errors without knowing these two mechanisms might be a daunting task, specially if they happen in the runtime pipeline much before a message gets to a handler or a controller. The first mechanism is the error policy. You can configure the error policy preferences as part of the configuration object (HttpConfiguration) in the IncludeErrorDetailPolicy property. This is just an enum that instructs Web API about how to deal with exceptions.