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Error c000021a

I was resetting permissions on my C drive to give everyone full control and the system hung. I rebooted and received the error message that autochk could not start, then I got a blue screen with the Fatal Error c000021a message. I tried to run it in safe mode and could not, I get the same message. I tried to go back to the last known good configuration and it still gave me the same error message.

I'm guessing my only choice is to reload Windows 2000 Professional. Any other ideas?

1 Solution
Note the following approcah will not replace any system files.

Can you boot to your Win2000 CD? If so then when it finally boots to the CD choose "Repair Console" this will allow you to use the command line. From here do something like this. Or if the file system is FAT32 you can use a Win98 bootdisk to do this. www.bootdisk.com

COPY /Y C:\WINNT\repair\RegBack\*.* C:\WINNT\system32\config\*.*

This will replace the registry to the last time the registry was backuped. Hopefully you didn't backup the registry at the time the problems started to happen.

Also if you desire not to copy over the entire registry you can do it one hive at a time. Following is a list of the files that are the registry hives. I would suggest starting with the System hive and then reboot and if the problem still persists do the Software hive next. Note these files don't have a file extension on them


I would suggest to first backup these hives from the C:\WINNT\system32\config\ to folder of your making
or choice just don't back them up to the C:\WINNT\repair\RegBack\ folder.  

You will probably need to reapply any services patches that you have previously installed.

Also you may want to take a look at this.

Differences Between Manual and Fast Repair in Windows (Q238359)

The Crazy One
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