[Macboatmaster]

It is not surprising to receive the critically low battery message , after draining the battery.
I know you were trying your best, but that was unlikely to achieve anything

I have little doubt that part of your problem is Norton, that is NOT to single out Norton. However the unquestionable evidence is that many if not all, third party Antivirus programs do not sit well with 10. They are OK at the start and then invariably produce problems, after major security updates to Windows and especially after version updates.

however to return to the issue at hand, it is often caused by shutting down whilst updates are in progress. It can however, also be caused by other third party software.
System cleaners, registry cleaner, boosters and the genre of - make it go faster programs are often to blame.

I suggest you start with a forced boot to recovery
That is power on
wait for the System event notification
power off
repeat three times
All being well your system will automatically load
Windows 10 options for recovery

power on the pc - power it off (by holding down the power button) while windows is still starting - repeat 3 times, then windows will recognize it as "boot failure" and go to the repair screen" ..

This will work if it commences the load of windows BEFORE the system event notification
You power OFF on the spinning circle for the commencement of the windows load.

If that DOES NOT work, when you reply I will offer other options

 

[Macboatmaster]

It is difficult to know what to try, not knowing what exactly did cause the issue

I suggest you try first startup repair

If it fails to repair on the screen that shows that message click advanced options and run it three times
as here
Run Startup Repair again:
Click/tap on Advanced options, and go to step 2 above. Sometimes it may take running Startup Repair up to 3 times and restarting the PC each time to fix the startup issue.

May I add - thank you to YOU for being appreciative

 

[Macboatmaster]

If everything IS Ok and all is working you are good to go
It was in view of your last post - a loss of connection I think during the installation of an update
If you use internet access via Bluetooth tethering again
PAUSE updates as here
https://support.microsoft.com/en-gb/help/4028233/windows-10-manage-updates

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All donated money will be used to pay for computer hardware, the Internet connection, server software, and other fees that apply directly to running the site.

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Mike Cermak
"TechGuy"

Thank you