This article describes an issue that occurs when you compress Windows image files in Windows 8.1, Windows RT 8.1, or Windows Server 2012 R2. A hotfix is available to resolve this issue. Before you install this hotfix, see the Prerequisites section.

Symptoms

When you try to compress the Windows Overlay Filter driver (WoF.sys) in order to compress Windows image files on a Windows 8.1-based computer, New Technology File System (NTFS) leaks memory, and Windows image files cannot be compressed.

Cause

The memory leak occurs because of an interaction between the WOF and the NTFS.

Resolution

Hotfix information

Important Do not install a language pack after you install this hotfix. If you do, the language-specific changes in the hotfix will not be applied, and you will have to reinstall the hotfix. For more information, see Add language packs to Windows.

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:

http://support.microsoft.com/contactus/?ws=supportNote 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.

Prerequisites

To apply this hotfix, you must have update 2919355 installed in Windows 8.1 or 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.

The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows 8.1 and Windows Server 2012 R2 file information and notes

Important Windows 8.1 hotfixes and Windows Server 2012 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 8.1/Windows Server 2012 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.3.960 0.17 xxx

    Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2

    RTM

    GDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information" section. MUM, MANIFEST, and the associated security catalog (.cat) files, are very important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.

For all supported x86-based versions of Windows 8.1

File name

File version

File size

Date

Time

Platform

Ntfs.sys

6.3.9600.17884

1,687,384

19-May-2015

20:01

x86

For all supported x64-based versions of Windows 8.1 and of Windows Server 2012 R2

File name

File version

File size

Date

Time

Platform

Ntfs.sys

6.3.9600.17884

2,022,736

19-May-2015

19:57

x64

For all supported Windows RT 8.1

File name

File version

File size

Date

Time

Platform

Ntfs.sys

6.3.9600.17884

1,495,904

19-May-2015

20:08

Not applicable

Additional file information

Additional file information for Windows 8.1 and for Windows Server 2012 R2

Additional files for all supported x86-based versions of Windows 8.1

File property

Value

File name

X86_784659d89b3ff423bc1cea6ac0592c39_31bf3856ad364e35_6.3.9600.17884_none_b74446047a0b6d37.manifest

File version

Not applicable

File size

692

Date (UTC)

19-May-2015

Time (UTC)

20:19

Platform

Not applicable

File name

X86_microsoft-windows-ntfs_31bf3856ad364e35_6.3.9600.17884_none_3b10e0fa38853a35.manifest

File version

Not applicable

File size

16,008

Date (UTC)

19-May-2015

Time (UTC)

20:22

Platform

Not applicable

Additional files for all supported x64-based versions of Windows 8.1 and of Windows Server 2012 R2

File property

Value

File name

Amd64_625371912d223765123ee5ba7d622cec_31bf3856ad364e35_6.3.9600.17884_none_ac7ab088a25e1716.manifest

File version

Not applicable

File size

696

Date (UTC)

19-May-2015

Time (UTC)

20:19

Platform

Not applicable

File name

Amd64_microsoft-windows-ntfs_31bf3856ad364e35_6.3.9600.17884_none_972f7c7df0e2ab6b.manifest

File version

Not applicable

File size

16,014

Date (UTC)

19-May-2015

Time (UTC)

20:25

Platform

Not applicable

Additional files for all supported Windows RT 8.1

File property

Value

File name

Arm_91c847564b5d938d1ba05b74b7235caa_31bf3856ad364e35_6.3.9600.17884_none_c0368600417b249d.manifest

File version

Not applicable

File size

692

Date (UTC)

19-May-2015

Time (UTC)

20:19

Platform

Not applicable

File name

Arm_microsoft-windows-ntfs_31bf3856ad364e35_6.3.9600.17884_none_3b135352388258fb.manifest

File version

Not applicable

File size

16,008

Date (UTC)

19-May-2015

Time (UTC)

20:19

Platform

Not applicable



Status

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

References

See the terminology that Microsoft uses to describe software updates.

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