Error 500 when calling AppTiles api

Question

I have a lot of SharePoint site-collections (SharePoint 2016 on-premises) where I installed my add-in. All is working correctly but there is a problem in a single site-collection.

In the problematic site the users get always error 500 when they call

https://the-problematic-site/_api/web/AppTiles?$select=Target

The problem is present only with normal users (readers or collaborators), the administrators can call the API without any problem. All the site-collection are provided with the same PowerShell routine.

I can't find the details of the error in the event viewer.

Thank you

Answer 1

Sorry for responding to my own answer. I checked that the user have rights to read some folders but does not have rights to read the site. So (quite obviously) the user need at least site read rights, and it works.