Windows 10 WCF issues with HTTP statuses 400.3 or 500.19

I've been working with the awesome Xamarin.Forms recently which was working just fine. I then needed to deploy a WCF service into my local IIS (my usual preference to IIS Express) for some testing. The virtual directory was created fine by Visual Studio, but I could not access the .SVC page.

It took a few minutes of deep thought to consider what was happening. It was a fairly new Windows 10 machine that had IIS installed, but, Windows is now very locked own out-of-the-box, so I realised that it still didn't have the features needed to activate a WCF service!

This manifested itself firstly in a HTTP 500.19 error (which usually means a web.config error) and secondly HTTP 400.3(invalid header).

If you open Programs and Features and then Add/Remove Windows features you can add WCF Activation and the WCF services you require. I also ran aspnet_Regiis.exe -i to be sure that my .NET versions were all correctly registered for use by IIS.

Once I installed the Windows features, everything started working fine. Hope this helps!