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
    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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  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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