Windows 10: Keeps restarting

My HP Pavillion keeps restarting after I had rebooted it. It has the HP loading screen, then goes to download windows. Then it shuts down abruptly restarts and goes back on a loop. I do not know how to fix this and I am very worried

:)

 

Hard drive/ OS issue

a guy suggested :

• shutdown
• unhooked HDD
• restarted
• yay !!
• reconnected HDD
• restarted
• yay !!

also , try method 3
How do I unlock the drive where Windows 10 is installed?

 

Inexplicable restarts

Thanks for your patient help and analysis, zbook. I'll step through some of your suggestions over the next few days - there's a lot to do and some look a bit hairy! That is, for a PC that is working sweetly right now...

Meanwhile, as requested in the BSOD thread (sorry, I misunderstood and posted there by mistake), I've attached both ZIP files.
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One step I did try right away was to answer your question about whether my BIOS is up-to-date. I had no success at the AMI site but did get some info from this commercial site:





It was one of the '9' (I counted 10) listed here:





Terry, East Grinstead, UK

 

MBR keeps corrupting after restart

I have a machine that when restarted or allowed to go into hibernation, I receive a missing/corrupted master boot record message and Windows doesn't boot. I am able to successfully repair the MBR each time using Windows recovery console, but I'm unable to determine what keeps making it happen.

Dell Latitude E6420
Windows 7 64bit

Steps performed so far: -besides fixing the MBR after each restart or hibernation
-ran system file checker sfc /scannow
-ran chkdsk
-verified that ACHI was enabled in the bios

If I can't figure this out I will end up just reinstalling the operating system, but I worried that the issue with just reoccur later down the line. Any advice/recommendations would be much appreciated.