Symptoms

Assume that you run an application that is developed by using Windows Filtering Platform (WFP) API on a computer that is running Windows 7 or Windows Server 2008 R2. When the application filters network traffic, the network connection is slow.

Cause

This issue occurs because the computer does not send TCP/IP ACK messages until a time-out occurs. This occurs when the driver for WFP filters data that the driver receives through the network. Therefore, the network traffic stalls the transfer of data when the TCP/IP ACK messages are delayed.

Resolution

Update information

How to obtain this update

Microsoft Update

This update is available from the Microsoft Update website:

http://update.microsoft.com

Prerequisites

To apply this hotfix, you must be running Windows 7 Service Pack 1 (SP1) or Windows Server 2008 R2 Service Pack 1 (SP1). For more information about how to obtain a Windows 7 or Windows Server 2008 R2 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

976932 Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2

Registry information

To apply this hotfix, you do not have to make any changes to the registry.

Restart requirement

You must 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 7 and Windows Server 2008 R2 file information notesImportant Windows 7 hotfixes and Windows Server 2008 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 7/Windows Server 2008 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

    6.1.760 1.17xxx

    Windows 7 and Windows Server 2008 R2

    SP1

    GDR

    6.1.760 1.22xxx

    Windows 7 and Windows Server 2008 R2

    SP1

    LDR

  • 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 for Windows 7 and for Windows Server 2008 R2" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are critical to maintaining the state of the updated component. 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 7

File name

File version

File size

Date

Time

Netio.sys

6.1.7601.17911

240,496

20-Jul-2012

18:33

Netio.sys

6.1.7601.22067

240,496

20-Jul-2012

18:36

Fwpkclnt.sys

6.1.7601.17514

187,776

20-Nov-2010

12:29

Tcpip.sys

6.1.7601.17911

1,292,144

20-Jul-2012

18:33

Fwpkclnt.sys

6.1.7601.22067

187,760

20-Jul-2012

18:36

Tcpip.sys

6.1.7601.22067

1,306,976

20-Jul-2012

18:36

For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

File name

File version

File size

Date

Time

Netio.sys

6.1.7601.17911

376,688

20-Jul-2012

19:31

Netio.sys

6.1.7601.22067

376,688

20-Jul-2012

19:27

Fwpkclnt.sys

6.1.7601.17514

288,640

20-Nov-2010

13:33

Tcpip.sys

6.1.7601.17911

1,913,200

20-Jul-2012

19:31

Fwpkclnt.sys

6.1.7601.22067

288,624

20-Jul-2012

19:27

Tcpip.sys

6.1.7601.22067

1,901,936

20-Jul-2012

19:27

For all supported IA-64-based versions of Windows Server 2008 R2

File name

File version

File size

Date

Time

Netio.sys

6.1.7601.17911

711,024

20-Jul-2012

18:10

Netio.sys

6.1.7601.22067

711,024

20-Jul-2012

18:27

Fwpkclnt.sys

6.1.7601.17514

483,200

20-Nov-2010

10:33

Tcpip.sys

6.1.7601.17911

3,791,728

20-Jul-2012

18:11

Fwpkclnt.sys

6.1.7601.22067

483,168

20-Jul-2012

18:27

Tcpip.sys

6.1.7601.22067

3,814,768

20-Jul-2012

18:27

Status

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

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

Additional file information

Additional files for all supported x86-based versions of Windows 7

File name

X86_65169096eeb6050afb7446275fd698a6_31bf3856ad364e35_6.1.7601.17911_none_1fb8552afca1518e.manifest

File version

Not applicable

File size

708

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

X86_b79bfd3ac96baaf4558197625d591379_31bf3856ad364e35_6.1.7601.17911_none_36f5f44e90491b89.manifest

File version

Not applicable

File size

702

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

X86_c590950256f92c152bbc4017d6b83b35_31bf3856ad364e35_6.1.7601.22067_none_ca854a45e8aa51b1.manifest

File version

Not applicable

File size

708

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

X86_d4fa977bee9cf992f3a16dfa27be51ec_31bf3856ad364e35_6.1.7601.22067_none_ff47354e0fdd537f.manifest

File version

Not applicable

File size

702

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

X86_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.17911_none_589fdd7b13924901.manifest

File version

Not applicable

File size

2,540

Date (UTC)

20-Jul-2012

Time (UTC)

18:55

File name

X86_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.22067_none_58f942a22cd342a5.manifest

File version

Not applicable

File size

2,540

Date (UTC)

20-Jul-2012

Time (UTC)

19:05

File name

X86_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.17911_none_b52282f7c4ab0298.manifest

File version

Not applicable

File size

3,780

Date (UTC)

24-Jul-2012

Time (UTC)

03:47

File name

X86_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.22067_none_b57be81eddebfc3c.manifest

File version

Not applicable

File size

3,834

Date (UTC)

20-Jul-2012

Time (UTC)

19:09

Additional files for all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

File name

Amd64_16ab0bd0e16424112c32d82ed8ca6ab0_31bf3856ad364e35_6.1.7601.22067_none_bbcac2e1b98e5555.manifest

File version

Not applicable

File size

706

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_2703e26f55ad1122b04184b1a8b30b44_31bf3856ad364e35_6.1.7601.17911_none_3543ae29ba2b3107.manifest

File version

Not applicable

File size

706

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_286d1a9b41c07764b37fe8e4221fd07e_31bf3856ad364e35_6.1.7601.17911_none_81a4ef77d5d82efb.manifest

File version

Not applicable

File size

712

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_2f9130859798c27bd63589b7a0f47e2c_31bf3856ad364e35_6.1.7601.17911_none_acdba4ff8995c41a.manifest

File version

Not applicable

File size

712

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_76c64ab1c0785e9f385c95ec5f7105bd_31bf3856ad364e35_6.1.7601.22067_none_ceafadcf91c2d1f3.manifest

File version

Not applicable

File size

712

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_7b5333b06488d998b67e10c36c831465_31bf3856ad364e35_6.1.7601.17911_none_19e001175970d165.manifest

File version

Not applicable

File size

1,066

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_a4ab5f3af0eb2438c6de74fb1119e4fd_31bf3856ad364e35_6.1.7601.22067_none_164ca20bea2b5404.manifest

File version

Not applicable

File size

1,066

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_a86d921624e281bbe508b6523540da1b_31bf3856ad364e35_6.1.7601.22067_none_721a9c48a2c6b853.manifest

File version

Not applicable

File size

712

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Amd64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.17911_none_b4be78fecbefba37.manifest

File version

Not applicable

File size

2,542

Date (UTC)

20-Jul-2012

Time (UTC)

19:54

File name

Amd64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.22067_none_b517de25e530b3db.manifest

File version

Not applicable

File size

2,542

Date (UTC)

20-Jul-2012

Time (UTC)

19:52

File name

Amd64_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.17911_none_11411e7b7d0873ce.manifest

File version

Not applicable

File size

3,784

Date (UTC)

24-Jul-2012

Time (UTC)

03:56

File name

Amd64_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.22067_none_119a83a296496d72.manifest

File version

Not applicable

File size

3,838

Date (UTC)

20-Jul-2012

Time (UTC)

19:57

File name

Wow64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.17911_none_bf13235100507c32.manifest

File version

Not applicable

File size

1,166

Date (UTC)

20-Jul-2012

Time (UTC)

18:42

File name

Wow64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.22067_none_bf6c8878199175d6.manifest

File version

Not applicable

File size

1,166

Date (UTC)

20-Jul-2012

Time (UTC)

18:51

Additional files for all supported IA-64-based versions of Windows Server 2008 R2

File name

Ia64_0ab28e7effce5e8e0a6caea2acdc8db4_31bf3856ad364e35_6.1.7601.22067_none_05e171448b017606.manifest

File version

Not applicable

File size

1,064

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Ia64_50480b69d2c6b0165159a3fca18908c5_31bf3856ad364e35_6.1.7601.17911_none_f282113e2cb75969.manifest

File version

Not applicable

File size

1,064

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Ia64_e201713040c9b2d9cca65c7af2ac47fe_31bf3856ad364e35_6.1.7601.22067_none_8f4fdc959e8a2fb8.manifest

File version

Not applicable

File size

704

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Ia64_f15f5367f66760b2d3ef397306f851bf_31bf3856ad364e35_6.1.7601.17911_none_6c461bf169c0e5df.manifest

File version

Not applicable

File size

704

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Ia64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.17911_none_58a18171139051fd.manifest

File version

Not applicable

File size

2,541

Date (UTC)

20-Jul-2012

Time (UTC)

19:39

File name

Ia64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.22067_none_58fae6982cd14ba1.manifest

File version

Not applicable

File size

2,541

Date (UTC)

20-Jul-2012

Time (UTC)

19:40

File name

Ia64_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.17911_none_b52426edc4a90b94.manifest

File version

Not applicable

File size

3,782

Date (UTC)

24-Jul-2012

Time (UTC)

03:41

File name

Ia64_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.1.7601.22067_none_b57d8c14ddea0538.manifest

File version

Not applicable

File size

3,836

Date (UTC)

20-Jul-2012

Time (UTC)

19:45

File name

Wow64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.17911_none_bf13235100507c32.manifest

File version

Not applicable

File size

1,166

Date (UTC)

20-Jul-2012

Time (UTC)

18:42

File name

Wow64_microsoft-windows-netio-infrastructure_31bf3856ad364e35_6.1.7601.22067_none_bf6c8878199175d6.manifest

File version

Not applicable

File size

1,166

Date (UTC)

20-Jul-2012

Time (UTC)

18:51

Need more help?

Want more options?

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.