Yes, it's best to do a (Windows) update with the laptop having a full battery and connected to the mains to minimize the chance of an unexpected shutdown because of running out of power.
If it only does this when logging in into one specific Windows user, login to another one. But if it happens for all users or even before you see the login screen, there's not much else that can be done than going back to your latest image backup (if you made one, but why shouldn't you) or seeing what repair options you have when you boot from your Windows installation disc or stick (if you don't have that, you can download one).
If you need more help with these options, please give feedback.
I have a laptop and once my laptop shut off during an update.
Every time i log in it says error and then restarts.
Can you please tell me how to fix it.
Ps: its not a virus i already scanned it.

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