In Map Viewer Classic, attempts to add files such as CSV files and KML files using the Add Layer from File option fail, with the following error message returned:
The file, ‘<fileName>.<fileExtension>’, cannot be added to the map. The portal is not configured to support this file. Contact your portal administrator for assistance.
The image below demonstrates the error message returned after attempting to add a zipped file containing shapefiles in Map Viewer Classic.
Portal for ArcGIS is not federated with an ArcGIS Server site, and the ArcGIS Server site is not assigned as a hosting server.
Federate Portal for ArcGIS with an ArcGIS Server site and assign it as the hosting server. Refer to Portal for ArcGIS: Integrate your portal with ArcGIS Server for instructions.
If the error persists even if a hosting server is configured, ensure the server site is running.
If the server site fails to validate, ensure the ArcGIS Server service is running on Windows. On the server machine, navigate to Control Panel > Administrative Tools > Services.