part of the answer you can find here:
UNSOLVED Getting Error while searching an User
Getting Error while searching an User (in the Video you can see the error). How I can fix this?
on Debian 7 x64 with nodebb
Please update your redis database to 2.8.9 or higher. We use this command from redis 2.8.9
tried to update still same version. Got some special command for me?