ASP.NET Web Api HttpResponseException 400 (Bad Request) Hijacked by IIS

Question

I\'m writing a Web API service and trying to return a (400) Bad Request if my ModelState is invalid. I do not want a response body to be attached to this. It appears that II

Answer 1

Usually in such cases it is enough to set TrySkipIisCustomErrors = true on response object, but in case of Web API it sometimes doesn't do the trick (Web API even tries to set this flag internally by itself). For situations like this you can consider changing the IIS configuration. Please take a look here (you should be mostly interested in existingResponse="PassThrough").