Hatch just gave me the Bone of Ullr quest and opened a portal as he always does. Unfortunately, this particular portal lacks a way to interact with it, so I can't enter the quest area. In other words, Hatch's portal is merely backdrop - it doesn't have the usual "transit to dungeon" interface that the others had. The portals I create and the entrance to the Shadow Vault work normally, so the issue is just with Hatch's most recent one. If it matters, I picked up his quest right before I fought Ordrak (whom I just killed).
Any ideas on how to fix the problem would be appreciated.