I am publishing a restservice. In the call I set custom http headers. At this moment the preflight of this http request takes place: I should set the following 3 headers: Access-Control-Allow-Origin: my url Access-Control-Allow-Methods: POST, GET, OPTIONS Access-Control-Allow-Headers: custom headers At the moment I try to set these response headers in my published microflow when I inspect request with firebug I see that these response headers are not set. Where should I set these?