$ docker pull ngix
Using default tag: latest
Error response from daemon: pull access denied for ngix, repository does not exist or may require 'docker login'
I can pull other images (alpine, postgresql) from the library without problems. Hello world and other containers work well.
Ubuntu 17.10
Docker version 17.12.0-ce, build c97c6d6
Two years later and I’ve made the exact same mistake! (slightly different typo). Luckily I only spent 15 minutes as I was able to google and find this post