After recently installing VisualStudio 2013 Update 4, my current project that had previously worked quite well started saying that Windows Authentication were disabled, I knew that this was not true and after some debugging I found that anytime I tried to access the .SVC file with my browser it gave me the following exception
HTTP Error 403.14 – Forbidden
The Web server is configured to not list the contents of this directory.
After a quick spat to Google I was informed by Stackoverflow user J-T-R that IIS 8.5 had acted up similar for him and that he had resolved it by re-installing HTTP Activation.
HTTP Activation provides features required to run Windows Communication Foundation (WCF) services inside of IIS/ASP.Net that communicate over the HTTP transport.
Well that sounded spot on, I installed the package HTTP Activation feature in Windows features
And presto! My system were once more good to go. This bug seems to be a problem for users that currently were hosting WCF applications in IIS 8.5 before updating their IDE from VisualStudio 2013 Update 3 to Update 4.
//Hope it helps