Had an issue calling WCF service today. The following exception was being thrown when service was called:
WebHost failed to process a request.
The service '/InteliChartVendorCommunication/VendorService.svc' cannot be
activated due to an exception during compilation. The exception message
is: Security settings for this service require 'Basic' Authentication but it is
not enabled for the IIS application that hosts this service..
Ensured Basic authentication was indeed enabled in IIS before getting stumped on what actual issue could be. Turns out it was CustomErrors setting. Value was set to "off" vs "Off". Would have expected different exception from .NET (i.e. web.config parse exception) but it works now either way.