Jupyter Notebook - Cannot Connect to Kernel

Question

I've tried installing jupyter notebook using pip3 install jupyter. Every time i launch a new jupyter notebook, the notebook is unable to connect to the kernel. See screenshot below Attaching my requirements.txt file, also i'm on Python version 3.6.8. Jupyter version is 4.4.0 with notebook version 5.7.4.

Where did i go wrong here and how can i fix this? Thanks!

attrs==18.2.0
backcall==0.1.0
bleach==3.1.0
colorama==0.4.1
cycler==0.10.0
decorator==4.3.2
defusedxml==0.5.0
entrypoints==0.3
ipykernel==5.1.0
ipython==7.3.0
ipython-genutils==0.2.0
ipywidgets==7.4.2
jedi==0.13.3
Jinja2==2.10
jsonschema==3.0.1
jupyter==1.0.0
jupyter-client==5.2.4
jupyter-console==6.0.0
jupyter-core==4.4.0
kiwisolver==1.0.1
MarkupSafe==1.1.1
matplotlib==3.0.3
mistune==0.8.4
nbconvert==5.4.1
nbformat==4.4.0
notebook==5.7.4
numpy==1.16.2
pandas==0.24.1
pandocfilters==1.4.2
parso==0.3.4
pickleshare==0.7.5
prometheus-client==0.6.0
prompt-toolkit==2.0.9
Pygments==2.3.1
pyparsing==2.3.1
pyrsistent==0.14.11
python-dateutil==2.8.0
pytz==2018.9
pywinpty==0.5.5
pyzmq==18.0.0
qtconsole==4.4.3
scikit-learn==0.20.3
scipy==1.2.1
seaborn==0.9.0
Send2Trash==1.5.0
six==1.12.0
sklearn==0.0
terminado==0.8.1
testpath==0.4.2
tornado==6.0
traitlets==4.3.2
wcwidth==0.1.7
webencodings==0.5.1
widgetsnbextension==3.4.2

Example

Answer 1

There is a likelihood that you've updated Tornado to 6.0.0 recently. Try reinstalling it to version 5.1.1. It just helped me. Lost 1 hour of precious Saturday time on this.

Answer 2

Create a conda environment using:

conda create -n my_env python=3

Activate the environment using:

source activate my_env

Install the ipykernel using:

conda install ipykernel

ipython kernel install --name my_env --user

Now open the jupyter and select the "my_env" from Kernel option. ( path : jupyter -> kernel -> change kernel -> my_env )