It’s an error that can be very common in rest services but in this case it’s the classic worked on my machine but when deploying to a development server things started going wrong. At this point I’d like to say that ServiceStack.net isn’t the problem it’s a fantastic framework just coincidence :).
Looking over the web.config and IIS settings everything looked good. I wasn’t using anything that wasn’t on the server until I noticed the WebDAV Icon. This I found was the problem. After removing WebDAV from the server everything started working as required.
The short and curlys of it all, if you have this error check if WebDAV is installed and either remove it from IIS or remove it from “modules” and from “handler mappings”.