When you try to open a Jupyter notebook if you get the following error this this article explains what you need to do to fix it.
Error calling 'pyxll_jupyter.pyxll.open_jupyter_notebook'
The cause of this issue is a bug that was introduced into a dependency of Jupyter, traitlets. This bug was introduced after version 5.1.1 of traitlets and fixed in version 5.2.2. If you are seeing this error, it is likely that you have a version of traitlets installed between these two versions.
To fix this you should update Jupyter and its dependencies in your Python environment.
If you use "pip" to manage your Python packages use this command to update Jupyter and its dependencies to the latest version:
pip install --upgrade --upgrade-strategy eager jupyter
If you use conda, use the following command to update Jupyter and its dependencies:
conda update --update-deps jupyter traitlets
Once you have updated your Python environment you can check what packages are installed using "pip list" or "conda list". Check the "traitlets" package is not between 5.1.1 and 5.2.2, restart Excel, and this problem should be solved!
For more information about this issue you can see the original bug report, with the fixing pull request linked, here https://github.com/ipython/traitlets/issues/723.