docker build giving unauthorized: authentication required - docker

Question

My docker version is
Docker version 1.12.2-cs2-ws-beta, build 050b611
I am trying to build the image using command
docker build -t iis-dockerfile .
The DockerFile content is
FROM microsoft/iss
RUN echo "Hello World - Dockerfile" > C:\inetpub\wwwroot\index.html
config.json is
{
"auths": {
"https://index.docker.io/v1/": {
"auth": <somekey>
}
}
}
On running docker build, it gives error
Sending build context to Docker daemon 2.048 kB
Step 1/2 : FROM microsoft/iss
unauthorized: authentication required
I have already done docker login. That's how config.json is created. I am new to containers and following the get started tutorial https://blogs.msdn.microsoft.com/allthingscontainer/2016/09/15/windows-containers-getting-started-a-step-by-step-guide/. Any idea how can I work around this.
Also I figured out that docker pull is working for me. While this also required authentication

Answer 1

Just an observation. Make sure your docker file has correct base image name. Are you sure you want FROM microsoft/iss and not FROM microsoft/iis?
When I tried to create new image with correct base image. It seem to work.
Docker docker build -t test-iid .
Sending build context to Docker daemon 344.9 MB
Step 1/2 : FROM microsoft/iis
latest: Pulling from microsoft/iis
3889bb8d808b: Downloading
3430754e4d17: Downloading
7aee39cd34f9: Downloading [> ] 540 kB/122.7 MB
5b8e6b632025: Download complete
e067d71858d2: Download complete