Jupyter Lab Windows 10 no kernel connection.

Hello, I have looked for a solution to the problem but without success.

I have:
```
Windows 10
conda 4.8.3
Python 3.7.7
jupyter-client 6.1.3
jupyter-core 4.6.3
jupyterlab 2.1.5
jupyterlab-server 1.1.5
notebook 6.0.3
tornado 5.1.1
```

I run Jupyter inside a virutal environment (sbn) that is on my E disk: but it never connects to any kernel that I have available.


a few seconds later


```
(sbn)PS E:\Sebas\repositorios> jupyter notebook --no-browser --ip=0.0.0.0
[I 12:08:04.287 NotebookApp] JupyterLab extension loaded from E:\Sebas\Pyenvs\sbn\lib\site-packages\jupyterlab
[I 12:08:04.287 NotebookApp] JupyterLab application directory is E:\Sebas\Pyenvs\sbn\share\jupyter\lab
[I 12:08:04.472 NotebookApp] Serving notebooks from local directory: E:/Sebas/repositorios
[I 12:08:04.472 NotebookApp] The Jupyter Notebook is running at:
[I 12:08:04.472 NotebookApp] http://zeus:9999/
[I 12:08:04.472 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
[W 12:08:05.656 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=d7d12ca9-66ae-4381-aa21-e84c203ca520 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=d7d12ca9-66ae-4381-aa21-e84c203ca520 (10.0.0.10) 46.87ms referer=None
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=ee26392d-c21e-48b2-8b20-f3b59fef47e3 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=ee26392d-c21e-48b2-8b20-f3b59fef47e3 (10.0.0.10) 0.00ms referer=None
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=0fb7477b-c26e-4be0-8356-0f0cc036bcc8 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=0fb7477b-c26e-4be0-8356-0f0cc036bcc8 (10.0.0.10) 0.00ms referer=None
[W 12:08:05.703 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=5310feac-c5fb-4bd8-8039-914f8f7691d4 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:05.718 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=5310feac-c5fb-4bd8-8039-914f8f7691d4 (10.0.0.10) 15.62ms referer=None
[W 12:08:06.445 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=cc490c02-4538-4909-9c74-cda5be70fff6 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:06.445 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=cc490c02-4538-4909-9c74-cda5be70fff6 (10.0.0.10) 0.00ms referer=None
[W 12:08:10.665 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=82fdd7a6-372c-4e98-98ab-1058354288d2 (10.0.0.10): Kernel does not exist: 9d335f27-4d82-4142-a358-f60bab43cff0
[W 12:08:10.665 NotebookApp] 404 GET /api/kernels/9d335f27-4d82-4142-a358-f60bab43cff0/channels?session_id=82fdd7a6-372c-4e98-98ab-1058354288d2 (10.0.0.10) 6.51ms referer=None
[I 12:08:13.550 NotebookApp] Build is up to date
[I 12:08:14.535 NotebookApp] Kernel started: fa9d1e55-2707-4a6f-8a14-730bc5343731
[I 12:09:13.466 NotebookApp] Build is up to date
[W 12:09:15.875 NotebookApp] Timeout waiting for kernel_info reply from fa9d1e55-2707-4a6f-8a14-730bc5343731
[I 12:09:15.890 NotebookApp] Starting buffering for fa9d1e55-2707-4a6f-8a14-730bc5343731:4cd9c7f3-543e-4462-a036-d0673800ebfc
[I 12:09:15.906 NotebookApp] Starting buffering for fa9d1e55-2707-4a6f-8a14-730bc5343731:edc642fe-424e-4099-a6b6-10ef1f0f6c8f
[I 12:09:32.166 NotebookApp] Kernel started: ca30bb37-3f9e-48ac-895e-7baa245a41e0
[I 12:09:32.166 NotebookApp] Kernel shutdown: fa9d1e55-2707-4a6f-8a14-730bc5343731
[W 12:09:37.360 NotebookApp] 404 GET /api/kernels/fa9d1e55-2707-4a6f-8a14-730bc5343731/channels?session_id=2e7d3b18-ac2b-444c-af61-939540c37b88 (10.0.0.10): Kernel does not exist: fa9d1e55-2707-4a6f-8a14-730bc5343731
[W 12:09:37.363 NotebookApp] 404 GET /api/kernels/fa9d1e55-2707-4a6f-8a14-730bc5343731/channels?session_id=2e7d3b18-ac2b-444c-af61-939540c37b88 (10.0.0.10) 6.00ms referer=None
[I 12:10:14.471 NotebookApp] Saving file at /Untitled.ipynb
[W 12:10:47.671 NotebookApp] Timeout waiting for kernel_info reply from ca30bb37-3f9e-48ac-895e-7baa245a41e0
[I 12:10:47.678 NotebookApp] Starting buffering for ca30bb37-3f9e-48ac-895e-7baa245a41e0:fc40f649-c8ad-418c-a42b-c13910031ad5
[I 12:11:53.196 NotebookApp] Build is up to date
[I 12:12:02.182 NotebookApp] Kernel started: b5001e70-3901-47bf-863b-6f33a990a135
[I 12:12:02.198 NotebookApp] Kernel shutdown: ca30bb37-3f9e-48ac-895e-7baa245a41e0
[I 12:12:07.367 NotebookApp] Kernel started: 6339d9a5-977c-4791-a719-40654eecebf1
[I 12:12:07.367 NotebookApp] Kernel shutdown: b5001e70-3901-47bf-863b-6f33a990a135
[W 12:12:12.635 NotebookApp] 404 GET /api/kernels/b5001e70-3901-47bf-863b-6f33a990a135/channels?session_id=03503840-fcd0-42da-bfc4-3abaf2ed79d0 (10.0.0.14): Kernel does not exist: b5001e70-3901-47bf-863b-6f33a990a135
[W 12:12:12.635 NotebookApp] 404 GET /api/kernels/b5001e70-3901-47bf-863b-6f33a990a135/channels?session_id=03503840-fcd0-42da-bfc4-3abaf2ed79d0 (10.0.0.14) 0.00ms referer=None
[W 12:12:54.115 NotebookApp] Replacing stale connection: 6339d9a5-977c-4791-a719-40654eecebf1:03503840-fcd0-42da-bfc4-3abaf2ed79d0
[W 12:13:12.855 NotebookApp] Timeout waiting for kernel_info reply from 6339d9a5-977c-4791-a719-40654eecebf1
[I 12:13:12.870 NotebookApp] Starting buffering for 6339d9a5-977c-4791-a719-40654eecebf1:03503840-fcd0-42da-bfc4-3abaf2ed79d0
[I 12:13:55.887 NotebookApp] Saving file at /Untitled.ipynb
```

I have registered the Python (sbn) kernel, which was stored in the path C: \ ProgramData \ jupyter \ kernels \ sbn

```
{
"argv": [
"E: \\ Sebas \\ Pyenvs \\ sbn \\ python.exe",
"-m",
"ipykernel_launcher",
"-F",
"{connection_file}"
],
"display_name": "Python (sbn)",
"language": "python"
}
```

Start with the kernel spec at C:\ProgramData\jupyter\kernels\sbn and the NotebookApp logs showing repeated kernel_info timeouts and kernel shutdowns. Reproduce the Windows 10 setup and trace the selected Python (sbn) kernel from launch through its connection attempt. Done means the kernel remains running and responds to kernel_info so a notebook can execute cells.

Written by the indexing model from the issue text.