TMG Reverse Proxy using JSON RRS feed

  • Question

  • We are using TMG 2010 as a reverse proxy for some API-based services and all is good when HTTP 200's are returned.  When an HTTP 403 is returned, the TMG is not passing along the JSON error response, but instead wrapping the 403 with some HTML with the message "Error Code: 403 Forbidden. The server denied the specified Uniform Resource Locator (URL). Contact the server administrator. (12202)".  Since this is an API server, I want the pure JSON returned back to the client instead as shown below.  How do I disable the HTML responses for > 399 error codes and pass along the pure response?

      "request": "ZFNAp28ate",
      "code": "403",
      "message": "Bad timestamp format. Use UTC [yyyy-MM-dd'T'HH:mm:ss'Z']"

    Friday, July 1, 2016 10:30 PM