Why are we seeing a "The layer could not be loaded" error?

[LindsayKing1]

Hello All,

We have a 10.6 Enterprise Portal environment (on linux) that we are using to support our COVID-19 response efforts.  We've noticed an issue when layers from AGOL are added to a webmap.  After some research, the issue seems somewhat similar to this post, but in our case, we are building the webmaps from scratch, so ArcGIS Online assistant is not in the mix; nothing has been moved or copied over from elsewhere.

Here are our repro steps:

1) On our enterprise portal, create a new webmap

2) Add some content that is hosted on that portal and save the webmap

3) Close and re-open the webmap - no problem

4) Now add some content from AGOL (anything that is shared publicly) and save the webmap

5) Close and re-open the webmap - we get an Error: "The layer could not be loaded."

From what we can see, all the layers appear to load successfully, but what is the cause of this error?  We'd have thought we would be able to add publicly-shared content from AGOL no problem.

Thanks for any help you can offer.

Lindsay

FYI Natalie Campos‌

[JonathanQuinn]

You'll need to use Fiddler or your browsers dev tools when loading the map in order to figure out why the layer can't load. You should see requests for the service, and then be able to look at the response to see what's going wrong.