I've had some resurrected Dremora in tow for a while now, and they were pretty fun to fight with. But lately they've just... dissapeared. I know they're still alive somewhere because people keep commenting on how my magic is dangerous and to douse it... I've tried waiting for 3 days, no luck.

Any tips?

Did you fast travel? I know some of my zombies disappeared when i fast travelled to test it out.

I read something about this yesterday, its a bug and your thrall are still alive somewhere but unresponsive. Apparently the only cure for it is to change into a werewolf.

Forget that, just read the notes section at the bottom of this http://www.uesp.net/wiki/Skyrim:Conjuration it explains why and how to fix. Its says going to jail there fixes it but am sure i read turning into a werewolf does as well.

Yeah, I fast travelled, but I done that a lot. Sometimes they'd vanish for a day, and come back, but this time it seems they're lost somewhere in the province of Skyrim...