Azure - RoleEnvironmentException in OnStart

My previous post was a bit of rant at the developer experience in Azure when trying to set-up diagnostics. I managed to work out what was causing the rather unhelpful exception.

I was getting the following exception (message - 'error') when trying to start the app via the emulator:

This is caused by a missing configuration from the cloud config file(*.cscfg). Why it doesn't give a more helpful message is any bodies guess. The following highlighted line was missing from the config.

It might seem obvious once you know but when you're trying to grok something it ain't helpful when the exceptions are practically useless for diagnosing the problems...

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