Windows 8 Pro cannot boot - Error 0xC000021a

Anonymous
2012-11-25T18:10:13+00:00

Hi

I upgraded my son's laptop from Windows 7 to Windows 8 Pro. I has been working fine for a few weeks. But now when booting It halts iwth the error code 0xc000021a. I have tried the following options

Refresh - this fails with the error 0xc000021a

System Restore - this fails with 0xc000021a

Safe mode boot does not work

I can start the cmd console

Any suggestions as to how to proceed?

Windows for home | Previous Windows versions | Performance and system failures

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  1. Anonymous
    2013-01-12T09:08:49+00:00

    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.

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  2. Anonymous
    2012-11-25T21:46:18+00:00

    I have run into the same problem on a Lenovo Ideapad u410, has a hybrid drive setup with an SSD for cache and a 500GB traditionall HDD. 

    When I try refresh it tells me: "The drive where Windows is installed is locked.  Unlock the drive and try again.

    Reset: "Unable to reset your PC.  A required drive partition is missing."

    Automatic repair does not fix anything.

    Anyone have any ideas as well?

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  3. Anonymous
    2012-12-22T19:57:02+00:00

    I have the same problem on my HP desktop that we upgraded a few weeks ago from windows 7 to windows 8. A windows update came through that morning, and it rebooted then, but later that day, it never came back. Same error the above posts noted. Cannot go to desktop, cannot go to safe mode, cannot boot from recovery cd either. No system recovery or reset works. I managed to copy my personal files to another hard drive and back up to another computer, but my $1500 HP is useless. How can I fix the Windows 8 Error 0xc000021a without booting to desktop, from the command line?

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  4. Anonymous
    2013-01-17T04:43:04+00:00

    Hello, I am having this problem as well. Been running windows 8 on my desktop without issue for the past few months, and I got this problem all of a sudden.

    In my "C:\Windows\System32\LogFiles\Srt\SrtTrail.txt" file, it says

    "

    Root cause found:

    Bugcheck c000021a. Partameters = 0xfffff8a0052748a0, 0xffffffffc0000428, 0xfffff8a000486d40

    Boot critical file is corrupt.

    Repair action: File repair

    Result: Failed. Error code = 0x2

    Time taken = 5834 ms

    Repair action: System files integrity check and repair

    Result: Failed. Error code = 0x490

    Time taken = 641554 ms

    "

    Any ideas?

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  5. Anonymous
    2013-01-08T06:56:27+00:00

    I have the same problem right now, did you ever get it fixed? I only have one laptop and I have my life on it. And right now, it's completely useless. I am starting to rethink the Apple Mac, and I have never been a fan of Apple products. Never. But I can't do this. I need to have this fixed, I have all my work on it.

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