So I am on the conjuration ritual stone quest on PS3, and I go to the top of the hall of attainment, summon the dremora. He comes, I beat him up, and keep trying to talk to him, but he wont speak to me. Finally I kill him, he disappears in the same orb thing he appeared in, and thats it. I try to summon him a second time, but nothing happens. My character casts the spell, I have plenty of magika, so I have no idea why I can summon him again. Ive tried reloading, and the problem continues. any ideas?

Figured it out, its a glitch with barbas. If you have Barbas following you, the dremora will instantly attack him and not open dialog. No dialog, no way to complete the quest. Now, does anyone know how to keep barbas away from me while I do the quest? Im afraid if I tell him to stop following me then he is gone forever, but I want to hang onto him as long as possible. as annoying as he is, he serves as a great distraction for enemies because he is invincible.

Furthermore, I answered my own question again. If you have Barbas and a follower (I currently have J'Zargo), I commanded my follower to attack barbas in a different part of the college. while they are busy fighting, I completed the quest, then I fast traveled twice. By the second fast travel, Barbas and J'zargo showed up again, no longer fighting, and all is right in the world.