You cannot selectively restore files from a data deduplication backup in Windows Server 2012 R2 or Windows Server 2012

Gilt für: Windows Server 2012 R2 DatacenterWindows Server 2012 R2 StandardWindows Server 2012 R2 Essentials

This article describes an issue that occurs when data deduplication is enabled in Windows Server 2012 R2 or Windows Server 2012. A hotfix is available to resolve this issue. The hotfix has a prerequisite.


Assume that you have a data deduplication-enabled volume that contains a chunk store in Windows Server 2012. You back up some optimized files by using the Data Deduplication feature in Windows Server 2012. When you try to restore an optimized file, this issue occurs.

Note This issue also occurs in Windows Server 2012 R2 in which the volumes have the data deduplication feature enabled. This Windows Server 2012 R2 is upgraded from Windows Server 2012.


This issue occurs because certain optimized files are backed up incorrectly in Windows Server 2012 or Windows Server 2012 R2. Therefore, the deduplication pipeline sets the body size of the chunk store to zero. When you try to selectively restore a file, the body size of the chunk store cannot be determined, and the restore fails.

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 website: 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.


To apply this update, you must have update 2919355 installed in Windows Server 2012 R2.

Registry information

To use the hotfix in this package, you do not have to make any changes to the registry.

Restart requirement

You may have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


See the terminology that Microsoft uses to describe software updates.