Error: 404.17 – Dynamic content mapped to the static file handler via a wildcard MIME mapping.

I came across this error yesterday after installing Master Data Services on a 64bit Windows Server 2008 R2 box and trying to access the MDS WCF web service.  After a lot of messing around with mime types and handler mappings, running aspnet_regiis etc.  I noticed that the WCF activation feature was not installed.

This can be found here Server Manager –> Features –> Add Features.

As soon as I installed this feature the error went away.