You receive a "Stop error code 0x00000051" error message during registry restoration

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When you use programs that that perform registry backup and restore operations, your computer may stop responding, and you may receive the following error message:
BugCheck 0x51 (c, c0000005, bddbab34, bddba78c)

Arg1: 0000000c, (reserved)
Arg2: c0000005, (reserved)
Arg3: bddbab34, depends on where Windows bugchecked, may be pointer to hive
Arg4: bddba78c, depends on where Windows bugchecked, may be return code of HvCheckHive if the hive is corrupt.
CPU usage may also unexpectedly increase to 100% until you restart the computer. When the CPU usage is at 100%, any programs that use registry features may stop responding.
This problem may occur if you use a remote control program or a system backup program.

The RegRestoreKey function reads a specified registry hive file and copies it to a specified key in the System registry. The RegSaveKey function saves a specific registry key and all related subkeys to a hive file. Both functions perform operations on the System registry that must be performed exclusively. The problem that is described in this article occurs because the RegSaveKey and RegRestoreKey functions are called at the same time in a multi-thread program.

Windows 2000 hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


Microsoft Windows 2000

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version        Size       File name   ----------------------------------------------------------   19-Dec-2003  18:57  5.0.2195.6886     30,224  Mountmgr.sys   05-Feb-2004  20:37  5.0.2195.6897  1,699,776  Ntkrnlmp.exe        05-Feb-2004  20:37  5.0.2195.6897  1,699,200  Ntkrnlpa.exe        05-Feb-2004  20:37  5.0.2195.6897  1,720,000  Ntkrpamp.exe        05-Feb-2004  20:37  5.0.2195.6897  1,677,312  Ntoskrnl.exe
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section of this article.
For additional information about the RegSaveKey and RegRestoreKey functions, visit the following Microsoft Web site:For additional information about how hotfix packages are named, click the following article number to view the article in the Microsoft Knowledge Base:
816915 New naming schema for Microsoft Windows software update packages
824684 Description of the standard terminology that is used to describe Microsoft software updates

Article ID: 834728 - Last Review: 12/08/2015 05:58:00 - Revision: 3.0

Microsoft Windows 2000 Advanced Server, Microsoft Windows 2000 Professional Edition, Microsoft Windows 2000 Server

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