I\'m just getting started with docker. I\'m following the instructions specified here https://docs.docker.com/windows/step_one/
I installed docker (1.10.2) on window
For those who logged in via their email address associated with their account during the Docker desktop installation process - this problem seems to occur because the terminal has also stored those credentials, but for some reason it only accepts login's via your actual username.
If you go to DockerHub you should see it in the upper right corner.
Try running docker login with that username, and you should be all set!
docker login
# username from dockerhub
# the same password