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
    2013-01-17T05:40:43+00:00

    Have you installed new program? or changed any setting recently just before this happen?

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  2. Anonymous
    2012-11-26T13:28:50+00:00

    Hi,

    I have additionally looked at c:\windows\system32\Logfiles\Srt\SrtTrail.txt and see that the boot diagnostics pass successfully up to and including Internal state check. It states that the Root cause found is:

    Startup Repair has tried several times but still cannot determine the cause of the Problem.

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  3. Anonymous
    2012-12-17T10:37:04+00:00

    Just wondering if Arron's suggested fix worked.  The reason I ask is that his response is for a failure during the upgrade process from windows 7 to 8. Based on the information you provided, it sounds like you had your sons system up and running in windows 8 and some security update from ms was installed and after the usual reboot to complete the install, you got the 21a error. 

    Just wondering, it seems like maybe some people do not understand that an upgrade is different from an update.

    Off

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  4. Anonymous
    2013-01-25T22:50:38+00:00

    How do you do this as my pc is stuck and I cannot get to login

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  5. Anonymous
    2013-01-26T08:43:16+00:00

    I've got the same problem. New Laptop Dell with Windows 8 Home Edition preinstalled. 

    I can´t start my machine indeed from my DVD installation. PC reboot everytime with the same error.

    I've asked to DELL return my money or other operating system. Besides, i've had turn off my new  computer pressing power button several times. My advice is don't install windows 8 until windows don't fix this severe error.

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