Hi there,
until version 370 of the ArcGIS for AutoCAD plugin, we were able to connect to Feature-Services of our ArcGIS Server installation (no Portal installed). The recent version 400 does not seem to support direct access to ArcGIS-Server-Services. The only way seems to be to connect to ArcGIS Online or a local Portal-Installation. Is that right? Am I missing something? I couldn't find any hint online regarding this relevant change!
Thanks,
- Florian