I create a PDF file in a notebook and save it to disk.
When I try to download it via a link (<a href="{pdf_file}">Click here to download: {pdf_file}</a>) in the notebook I get a 404 not found error message.

it’s because a /files/ folder is added to the url when the link is generated, but I don’t know how to set it up, and creating a /files/ folder under the root is obviously not enough.

I have tried to specify folders in the jupyter_notebook_config.py file
by adding values such as :

c.ExtensionApp.static_paths = [os.path.join(os.environ['HOME'], 'files')]
c.ServerApp.extra_static_paths = [os.path.join(os.environ['HOME'], 'files')]
c.ServerApp.extra_static_paths = ['./files/']

In none of the cases, although the file is present in the indicated folder, can I download it.

What am I doing wrong?

Do you have an example that works?

my configuration:
Selected Jupyter core packages...
IPython          : 8.1.1
ipykernel        : 6.9.1
ipywidgets       : 8.1.3
jupyter_client   : 7.4.9
jupyter_core     : 5.7.2
jupyter_server   : 2.14.1
jupyterlab       : 4.2.2
nbclient         : 0.5.11
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 7.2.1
qtconsole        : 5.2.2
traitlets        : 5.14.3

Thanks