To be able to open .ipynb jupyter notebook files with a simple doubleclick on them run this in the command line:
pip install nbopen python -m nbopen.install_win
This will reuse existing jupyter server if possible (=if it is already launched in the same dir).
Alternatively, you can associate ipynb with jupyter-notebook directly:
Run this command in cmd.exe under administrator privileges:
assoc .whl=jupyter& ftype jupyter=cmd.exe /c jupyter-notebook "%1"
Alternatively, a slightly different line can be copied into a assoc_ipynb.bat file and executed through 'Run as administrator':
assoc .whl=jupyter& ftype jupyter=cmd /c jupyter-notebook "%%1"
PS jupyter-notebook.exe is assumed to be in the PATH.