I use an InvokeHTTP processor to POST login details to a website This returns a Set-Cookie attribute Then I use another InvokeHTTP to request some JSON from a REST endpoint. I have created a Cookie attribute as ${Set-Cookie:substringBefore(';')} and added Cookie to "Attributes to Send" to use it as an HTTP header. The problem is that this 2nd InvokeHTTP fails authentication and returns a 401. If I manually log in and copy the Cookie value to the 2nd InvokeHTTP's parameters, the call works. In either case the Data provenance shows a valid Cookie value but the call always returns a 401 when the value comes from the dynamic value, so I am a bit lost. ... View more