Error when executing `jupyter notebook` (No such file or directory)

For me the issue was that the command jupyter notebook changed to jupyter-notebook after installation.

If that doesn't work, try python -m notebook, and if it opens, close it, then export PATH=$PATH:~/.local/bin/, then refresh your path by opening a new terminal, and try jupyter notebook again.

And finally, if that doesn't work, take a look at vim /usr/local/bin/jupyter-notebook, vim /usr/local/bin/jupyter, vim /usr/local/bin/jupyter-lab (if you have JupyterLab) and edit the #!python version at the top of the file to match the version of python you are trying to use. As an example, I installed Python 3.8.2 on my mac, but those files still had the path to the 3.6 version, so I edited it to #!/Library/Frameworks/Python.framework/Versions/3.8/bin/python3

It seems to me as though the installation has messed up somehow. Try running:

# For Python 2
pip install --upgrade --force-reinstall --no-cache-dir jupyter
# For Python 3
pip3 install --upgrade --force-reinstall --no-cache-dir jupyter

This should reinstall everything from PyPi. This should solve the problem as I think running pip install "ipython[notebook]" messed things up.