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Defrag task does not work on a deduplicated VHD file in Windows 8.1 or Windows Server 2012 R2

View products that this article applies to.


Consider the following scenario:
  • You run a virtual machine (VM) by using a VHD file that is not deduplicated.
  • You run a dedup job to deduplicate the VHD file.
  • You run a task in the VM that performs many write tasks on the VHD file and causes many recalls on the deduplicated file.
  • You run the defrag task.
In this scenario, the defrag task does not defragment the VHD file.

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To resolve this issue, install update 2955164. For more information about how to obtain update 2955164, click the following article number to view the article in the Microsoft Knowledge Base:
2955164 Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 update rollup: May 2014

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

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More Information

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
This issue occurs because the Cluster Shared Volumes File System (CSVFS) volume does not unpin a file after the dedup job sets a reparse point on the file

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Keywords: kb, kbqfe, kbfix, kbsurveynew, kbexpertiseadvanced

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Article Info
Article ID : 2958287
Revision : 1
Created on : 1/7/2017
Published on : 5/13/2014
Exists online : False
Views : 279