I'm trying to build a Delphi Unit to access the GW Rest Interface (did the same with the SOAP API - this works very well). As the Delphi REST Components need official certificates, I cannot use them. Instead I use the same libraries that I'm using for SOAP (Lazarus synapse with OpenSSL-dlls).

But no matter what request I send to the REST API, I allways get back a status of 500. There is one example, I tried a lot of others:

GET /list/USER HTTP/1.1
Host: mail.bond.de:9710
Keep-Alive: 300
Connection: keep-alive
User-Agent: Mozilla/4.0 (compatible; Synapse)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Upgrade-Insecure-Requests: 1
Cache-Control: max-age=0

I added those header fields after doing a request with Chome and checking the request data of chrome. But in any combination, with or without the headers, with or without the Authorization header, I always get an Statuscode of 500 back. I checked the network communication with wireshark and saw encrypted packets.
I set the logginglevel of gwadmin-service to debug - I can see actions done with a browser (e.g. /list/USER ) but not the requests of my program.

What can I do to find out, what is needed ?