added new user no shell/ tab completing
sounds like your user was added with the sh shell instead of bash try the following.
su to your new user and type chsh type /bin/bash and press enter
now try reloging and see if it works
I encountered the same problem and I managed to correct it with useradd itself. Indeed, you can set the initial shell for the user while creating the user, with -s option:
useradd -s /bin/bash -d /home/newname -m newname