Called B sods  (BSOD)

Not blackscreens! with funny geek like messages in white  text? (has the words STOP,  DUMP? or HALT  ?)    The best place to look is here livewire.
Learn the F8 key (or via menu's) will in fact do a MAGICAL COLD BOOT ( a true to life real cold boot)! Do that first, please.

If using Window10 see this common failure of W10 not wanting to recover,  due to the silly way fast-startup (quick boot ) works. (how to force F8 mode in W10 is the cure!)

Microsoft now adds  51+ more Blue screens of death just for fun in W10, some are serious, and some are just windows doing and update, the only clue is blue windows. and some words. (no logo shown, except errors with 3D bar codes)
I show a few screens here just to show, most never tell you its MICROSOFT CODE TALKING TO YOU.
Relic BSOD seen in photo 3 below..  "Classic for 25 long years"  Most times this is a Virus or bad Video driver or bad RAM. (or other chips, I had a bad SATA chip that did this)

Try a LIVE PE or Linux boot stick or CD see if PC now runs OK,? if does that tells you your boot main SSD/HDD drive has corrupted windows files. (or drivers wrong) or even a bad HDD (hard disk drive or SSD, solid state drive)
Note that in each case Microsoft fails to tell you, who owns the screen, not even a tiny MS icon or icon flag. (silly to a fault this, and confuses MILLIONS)
First is W10 crashing, most times this is a bad video driver, in the HAL.
One other reasons for windows 10 failing is upgrading XP or W7/8 to 10.  Due to these vast complexities of HP restored OS to like new (F11)
W10.  Most times GPU drivers munged. Note the asinine , no clue of what entity did this, (it's MICROSOFT) MS thinks they OWN THE COLOR BLUE?
W10 failing one can us a CELL CAM to find what 3d bar means. (omg a clue its MS  ) what next a icon of gill bates?>

This is the Classical  BSOD, XP to W7 are the most common. (sometimes bad RAM here) mostly rare on and new and not infected PC. 
The next screen  is not icon marked either, and is serious corruption of the OS .
W10 here,  Fails to say MS is working on updates.  Dang me..!
And last and most common now, the endless, Microsoft updates, it was again too much trouble for Microsoft  to at least put MS,  between on and updates "Working on MS Updates"  is hard for them. It's a secret. I guess.
By far the most common screen you will see is NEXT MS UPDATES:

This takes up to 10 minutes on my 200mbps fiber connected PC,  or 5 Days using Dial up.  5GB is size of last huge update.
Warning you can get black screens for a while doing some MS updates.  (this happens at a reboot, during an UPDATE, it's kinda ,a DOS mode update, no windows shells running)
The Hard disk failing can also show a blue screen warning of HDD death soon, (it sees gross S.M.A.R.T data errors) Trust this it's not fibbing.

If you can not get Windows to start, use the F11 restore mode (steps. power off, power on, hammer F11, until HP restore pages pop seen below)
Then pick this. Advanced options: Then Automatic repair. This will patch the boot strap files.
The restore is last resort, make PC like day 1 new. (all your data is lost now)

Windows can start run and run slow or run and crash or do many things corrupted or virus infected.
Besides spending all day  running virus scanners, (top 10) I can run SFC /scannow (run in cmd.exe command prompt window) SFC means System File Check.
I can examine all startup files.
But ,you can be just overloaded with startup files. 
The Microsoft scanner below uses "VIRUS TOTAL CLEAN" to check each file for infection, what  great tool this is !!!
The best program for this (besides my loved "Security Task manager pro" app) is the Microsoft version of Autorun , as seen here.(portable too, it is)
Running the ONLINE ESET AV scanner is very powerful. (best I've ever seen)
Run Malwarebytes, for free. (google it )

KNOPPIX rules:
In all cases of crashing WINDOWS, I use my Linux live boot stick (Knoppix ! 7) and my MS Windows 7 PE live disk or usb stick (from ISO file).

I  power on hammer F9 key and see the boot menu, (live boot choices) and pick my stick of choice.
I now can run disks tests. and see if the live OS stick (or cd or dvd) run clean. 
If the BOot stick passes all my tests for sure the knoppix HARD disk checker, then the HDD0 is infected, or corrupted, the solution is obvious, reload, WINDOZ.


version 1.  5-9-2017