Not like I'm always going to the soul cairn anyway. I've tried a couple of other saves but nothing works.
The undercroft was originally an old escape tunnel out of the castle. The Volkihar Dungeons include Volkihar Undercroft, Volkihar East Tower, Volkihar North Tower, and Volkihar Ruins. They are distinctly separate from the living quarters of the castle and is host to several hostile occupants.
That would too many hours to redo though. The Volkihar Dungeons is a location in The Elder Scrolls V: Dawnguard. There aren't really any saves before I killed Harkon which I presume would be far enough back. When you reach the Volkihar Courtyard, Serana will comment that something seems to be wrong with the moondial in the center (5), and shell speculate that it. Then reinstall the add-on and you'll be able to start it from the beginning again. This will delete ALL items and quests related to Dawnguard. start the game and when queried, say 'yes I want to play anyway'. If all else fails and you can't live with the bug, you CAN uninstall the add-on. If this bug occurs, just get out of the conversation, he will still do it.' Only for PC and PS3: 'When asking if he may be allowed to reconstruct the passage to the garden, he may be stuck in the last sentence, and the dialogue option will forever be gone, it is unknown what causes this. The wiki has no real wisdom to give on this bug.