I'm not able to render ArcGIS Server 10.4.1 map services in ArcGIS Portal 10.5.1 Scene viewer. Google Chrome Developer tool displays this error:
Failed to load https://<DOMAIN_NAME>/arcgis/rest/info?f=json: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://<DOMAIN_NAME>' is therefore not allowed access. The response had HTTP status code 401.
<DOMAIN_NAME> is a actual value in the error. This is a CORS related issue. I have added "Access-Control-Allow-Origin" with value "*" in IIS for both the Portal and ArcGIS Server instances but no joy.
The ArcGIS Server 10.4.1 instance will soon be upgraded to 10.5.1.
What I really need to know is if this is a known issue and will the upgrade to 10.5.1 eliminate the problem.