Ok..
Ive just tried something and got this at http://{server}/hap/api/setup:
Server Error in '/HAP' Application.
--------------------------------------------------------------------------------
Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.
Parser Error Message: An endpoint reference cycle was detected in your configuration. The following reference cycle must be removed: webHttpEndpoint/, webHttpEndpoint/.
Source Error:
Line 242: <standardEndpoints>
Line 243: <webHttpEndpoint>
Line 244: <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="true" faultExceptionEnabled="true">
Line 245: <security mode="Transport"/>
Line 246: </standardEndpoint>
Source File: C:\inetpub\wwwroot\HAP\web.config Line: 244
--------------------------------------------------------------------------------
Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1

