When registering a custom widget what does the error message "The URL does not reference an AppBuilder Extension" mean? What should be referenced?

[ChristopherBertrand]

We recently needed to rebuild our 10.9.1 Enterprise system from scratch after an failed upgrade from 10.7.0 and are encountering a roadblock when trying to register a custom widget to our Portal. I follow the directions as per the Esri Add Custom Widgets document for Enterprise 10.9.1 but receive the error message "The URL does not reference an AppBuilder Extension."

I have had some concerns from the start given that the menu lacks the Title and Tags options from the example in the directions and all the examples in the various help postings and videos I've found while searching for a solution.

I had no problems registering custom widgets previously with instructions I received from a colleague - 

"Un-zip the widget folder, you should be able to copy that entire folder (such as eSearch - with all the items within it) and paste it on the C drive of the Portal server at:     C:\inetpub\wwwroot

Then, look at the 'manifest.json' file, and follow the instructions for Add a Custom Widget, starting at the 'Register a custom widget' section."

In that location the widget files should be publicly available and avoiding the issue referenced in the  BrianVan_Nostrand post:

"The URL doe not reference an AppBuilder Application" when deploying custom web application

What does "The URL does not reference an AppBuilder Extension" mean? What should be referenced and how?

[IhabHassan]

HI @ChristopherBertrand 
Try to browse the manifest.json URL in the browser, are you able to see JSON file content?

[ChristopherBertrand]

No, I am not.  I only get a HTTP Error 404.  Is there a setting I need to change to make the file location network accessible?

[IhabHassan]

Usually JSON is added by default to IIS as a mime type that it can serve, but worth checking at your side.

I noticed that the widget URL shown in the screenshot look a bit interesting. The easiest way to get the correct URL is to try to select it from IIS content view, then right click and choose "Browse". This should open the file in the browser, you can then use the URL to register the widget with ArcGIS Enterprise.

[ChristopherBertrand]

Thank you IhabHassan, that was the sticking point.  I used Browse as you advised and the resultant URL was a truncated version of what I was trying to use.  As TonyContreras_Frisco_TX's post mentions in a wonderfully concise way, the portion "inetpub/wwwroot" in my path was gumming up the works.  I replaced localhost in the browsed URL and Portal accepted the entry.  Thank you both!

[TonyContreras_Frisco_TX · Accepted solution]

Looking at the image you shared, I see the URL you provided includes "inetpub/wwwroot" however that part of the path is ignored by IIS. If you have a "Measure" folder in C:\inetpub\wwwroot, can you access https://yourdomain.com/Measure/manifest.json ?