Hi friends, I tried add a ".slpk" as item in my Portal 10.5 but when I clicked in "ADD ITEM" nothing happens. I tried this action in AGOL and works correctly.
Has this happened to anyone?
Can you please make sure that the Tile Cache Data Store that is configured with your hosting server validates from ArcGIS Server Manager?
Traditionally, I would expect to see the option to publish the SLPK as a hosted scene layer in the window in your screenshot. Since this is not the case, something tells me it may be an issue with the Tile Cache Data Store.
Other information that would be useful: