Win10 running EXTREMELY slow after being unplugged all day

Its running so slow, i started this thread on my PC, and typed the subject in blind (as the keyboard strokes are so delayed, its still typing the thread subject now while i do this on my phone).

Its been unplugged all day as an electrician has been round.

Turned it on, and its completely unusable.

I’ve tried Media Creation, it downloads Win10, and Creates the files (the second step that counts upto 100%),
It then closes, and nothing then happens.

Pretty desperate, this is my work, stream and gaming computer!!

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Going to try this:
https://support.microsoft.com/en-us/...a-a97a1807f3dd

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Okay, rebooted in a clean environment by disabling all non-MS services and disabling all start up programs, still extremely slow. 😭😭

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Booted in safe mode, on desktop loading I got

ctfmon.exe - success
Unknown Hard Error

And it keeps popping up when I click OK.

But the machine feels fast again... so what’s next?

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Okay, i thought id boot it in diagnostic mode, got to the PIN screen... says I need to set up a pin, i click set up, and it asks if i want to search for the app in the store.

I does nothing... im just panicking now...

Please explain: Its been unplugged all day as an electrician has been round.

Do you have a HDD or SSD or both?
Did you do a disk check?
Open a CMD window as administrator and type:
chkdsk c: /f
It will say your disk is in use and if you want to schedule to next start = yes
Restart
Pay attention on the results, specially bad blocks, bad clusters, bad sectors etc