Unable to start jupyter notebooks via terminal

[mmoser18]

I installed Jupyter notebooks as instructed, i.e.

• Download Anaconda Distribution (a few 100MB), Python 3, 64 bits
  

• Install it using the default settings for a single user.
  

But - while I can start the Jupyter Notebook App via the Windows menu - trying to start it using the cmd-line, i.e. entering "jupyter notebook" in a newly opened cmd window just yields:

C:\Users\mmo>jupyter notebook
_cffi_ext.c
Anaconda3\lib\site-packages\zmq\backend\cffi\__pycache__\_cffi_ext.c(213): fatal error C1083: Cannot open include file: 'sys/un.h': No such file or directory
Traceback (most recent call last):
  File "C:\Users\mmo\Anaconda3\Scripts\jupyter-notebook-script.py", line 6, in <module>
    from notebook.notebookapp import main
  File "C:\Users\mmo\Anaconda3\lib\site-packages\notebook\notebookapp.py", line 47, in <module>
    from zmq.eventloop import ioloop
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\__init__.py", line 47, in <module>
    from zmq import backend
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\backend\__init__.py", line 40, in <module>
    reraise(*exc_info)
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\utils\sixcerpt.py", line 34, in reraise
    raise value
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\backend\__init__.py", line 27, in <module>
    _ns = select_backend(first)
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\backend\select.py", line 28, in select_backend
    mod = __import__(name, fromlist=public_api)
  File "C:\Users\mmo\Anaconda3\lib\site-packages\zmq\backend\cython\__init__.py", line 6, in <module>
    from . import (constants, error, message, context,
ImportError: DLL load failed: The specified module could not be found.

C:\Users\mmo>

What am I missing? Or rather: what is this installation instruction missing?