Windows 8 Pro cannot boot - Error 0xC000021a

I've dealt with this problem twice on the same laptop already. one was on 8 and another time with 8.1.

if you have the simplest version of this problem Amir's solution will work, if not then you probably hve the nasty kind that's HELLA HARD to find n get rid of.

plan on working in CMD for awhile. forums leading you to other fourm after forum. The problem is one of the security updates from microsoft and usually it will show after an auto-update.

here's a shortcut. open up CMD as an administrator.:::: (I couldn't use the "online" command so change it to whatever your hard drive is on usually :C:\ write everything down as it says so you dont screw up a line. start deleteing your current updates. I would do them all!! then run some test after like SFC /scannow and any others and try restarting in safe mode. it worked for me but be ready to ease her back to life. if you get to the desktop make backups or copy files or whatever you have to and restart.

Works on Windows Server 2008R2, 7, 8 and higher

1. Find the list of packages installed on the machine with the issue by performing this command

Code:

dism /online /get-packages /format:table

2. From the list get the Package Identity Name

Code:

Package_for_KB2870699~31bf3856ad364e35~amd64~~6.2.1.1

3. Run this command to uninstall the update silently

Code:

DISM.exe /Online /Remove-Package /PackageName:Package_for_KB2870699~31bf3856ad364e35~amd64~~6.2.1.1 /quiet /norestart

google images of what you should be seeing

I'm actually glad I wasn't alone in finding this as a solution. But Now however, doing so now doesn't seem to be helping as I am stuck once again in another loop. It proceeds to restart after "disabling driver signature" and returns yet again to the "Blue screen of Death". I need assistance!

I'm in startup repair and now my system has frozen. I have no idea how to fix computers. PLease help 

Do you mean your system is frozen when you get to startup repair? if yes, well, it should be something else and you have to contact your system admin or official Microsoft support team.

i had this problem and i fixed it. i faced this after updating my win8 and rebooting after that update.

to fix this, i tried safe mode but it failed to boot. finally i tried to boot with "force drivers to have signature disabled" and it worked.

How do you do that??? I have tried to do everything but I don't know how to get to that part.

Based on your PC or Laptop, you should press F8 or F6 or F2 or F12 just after you turn on the device, this is how you will be redirected to advanced boot menu options.

Why on earth did they create Win 8?

It has caused me so much grief. Bought a MS Surface Pro 3 - Win 8 has prevented it and me from being friends.

Now this "error 0xc000021a" has stopped what little progress I was making. I ama NOVICE at solving these problems.

I just googled the error and will try the automated suggestion: (Download (0xc000021a) repair utility.

Keeping my fingers crossed when I try it ....

How'd you even get to windows without starting up???