Avanchnzel

[lioba999]

Where do I get teh key to unlock the double doors in Avanchnzel to take the Lexicon back?

[frogprincess_q4]

This includes a walk through.

http://www.uesp.net/wiki/Skyrim:Unfathomable_Depths

[lioba999]

I cannot get into the last chamber. It is locked, requires a key. How do I acquire the key?

[frogprincess_q4]

I don't remember needing a key here. You have the Lexicon, I assume? And you can't get through the door right after the spinning blades? So you can't return it? Is the quest marked as active? Perhaps try leaving the dungeon and the reentering see if that triggers the door unlocking.

You could also try to use console to unlock the door or possibly use tcl to go through it. There are several walkthroughs online for this dungeon including video ones. I'm sorry I can't be more helpful than that.

[lioba999]

I left the quest for a week or so, came back, & the door was open - quest completed! Thank you!