So I was doing this quest today, after going trough all the draugr to get this horn, I get a note saying I need to meet with someone at the Sleeping Giant Inn.
I go there, talk to the bartender but he says I need to talk to Delphine to rent a room. Meanwhile, Delphine is stuck in the same spot in Dragonreach, in the court mage's room.
When I try to approach her, she only replies with "Hmm?" everytime and I can't start a conversation.

I don't know if this bug was addressed here before, but I googled a fix before posting here, and even though I found some people with the same problem I didn't find any fixes.
I tried disabling and enabling Delphine with the console, as mentioned in other places, I tried advancing the quest using the console commands from UESP wiki, but nothing works.

So if anyone knows a real fix to this, I would be grateful.

Sigh.. back to sidequests..

Have you tried waiting a few days (long enough for cells to reset) then attempting to speak with her?

BTW, Welcome to the forums, http://images.uesp.net/c/c4/Fishystick.jpg

never came across that bug before. if she is stuck on something in dragonsreach can you "push" her away from it?