Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

Applications can't communicate over TCP loopback path in Windows 8.1 or Windows Server 2012 R2


View products that this article applies to.

This article describes an issue that blocks communication over a TCP loopback path for applications in Windows 8.1, Windows RT 8.1, or Windows Server 2012 R2. An update is available to fix this issue. Before you install this update, see the Prerequisites section.

↑ Back to the top


Symptoms

When this issue occurs, the loopback TCP packets fall from a fast path to a slow path and are then dropped. 

↑ Back to the top


Cause

This issue occurs because of an incorrect checksum.

↑ Back to the top


Hotfix information

Important If you install a language pack after you install this hotfix, you must reinstall this hotfix. Therefore, we recommend that you install any language packs that you need before you install this 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's described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there's a "Hotfix Download Available" section at the top of this Knowledge Base article. If this section doesn't appear, submit a request to Microsoft Customer Service and Support to get 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 don't 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 don't see your language, it's because a hotfix isn't available for that language.


Prerequisites

To apply this hotfix, install update 2919355 in Windows 8.1 or Windows Server 2012 R2.

Registry information

To use the hotfix in this package, you don't 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 doesn't replace a previously released hotfix.

↑ Back to the top


Status

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

↑ Back to the top


References

Learn about the terminology that Microsoft uses to describe software updates.

↑ Back to the top


File information

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables. The dates and times for these files are listed in Coordinated Universal Time (UTC). Be aware that dates and times for these files on your local computer are displayed in your local time and with your current daylight saving time bias. The dates and times may also change when you perform certain operations on the files.
Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2
Notes
  • 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:
    VersionProductMilestoneService branch
    6.3.960 0.17 xxxWindows RT 8.1, Windows 8.1, and Windows Server 2012 R2RTMGDR
    6.3.960 0.18 xxxWindows RT 8.1, Windows 8.1, and Windows Server 2012 R2RTMGDR
  • 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 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.
Windows RT 8.1
File nameFile versionFile sizeDateTimePlatform
Fwpkclnt.sys6.3.9600.17336278,86408-Sep-201401:20Not applicable
Tcpip.sys6.3.9600.181241,759,59210-Nov-201506:12Not applicable
x64 Windows 8.1 and Windows Server 2012 R2
File nameFile versionFile sizeDateTimePlatform
Fwpkclnt.sys6.3.9600.17903428,88811-Jun-201520:12x64
Tcpip.sys6.3.9600.181242,474,84010-Nov-201506:01x64
x86 Windows 8.1
File nameFile versionFile sizeDateTimePlatform
Fwpkclnt.sys6.3.9600.17485286,52810-Nov-201417:47x86
Tcpip.sys6.3.9600.181241,852,24810-Nov-201506:06x86

Additional file information
Windows RT 8.1
File propertyValue
File nameArm_497393c0c4a1ee39545723a197b955ad_31bf3856ad364e35_6.3.9600.18124_none_512fafa6916ff48e.manifest
File versionNot applicable
File size702
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
File nameArm_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.3.9600.18124_none_4800f75d81cc8648.manifest
File versionNot applicable
File size3,883
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
File nameUpdate.mum
File versionNot applicable
File size1,610
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
x64 Windows 8.1 and Windows Server 2012 R2
File propertyValue
File nameAmd64_00d951a165807255209f869bece77e12_31bf3856ad364e35_6.3.9600.18124_none_6b84df93eb7c11b3.manifest
File versionNot applicable
File size706
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
File nameAmd64_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.3.9600.18124_none_a41d20893a2cd8b8.manifest
File versionNot applicable
File size3,887
Date (UTC)11-Nov-2015
Time (UTC)00:32
PlatformNot applicable
File nameUpdate.mum
File versionNot applicable
File size1,618
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
x86 Windows 8.1
File propertyValue
File nameUpdate.mum
File versionNot applicable
File size1,610
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
File nameX86_d6c0173338a38ab3028693cdeb17eeb4_31bf3856ad364e35_6.3.9600.18124_none_3bae2a1bd68efb0b.manifest
File versionNot applicable
File size702
Date (UTC)11-Nov-2015
Time (UTC)00:25
PlatformNot applicable
File nameX86_microsoft-windows-tcpip-binaries_31bf3856ad364e35_6.3.9600.18124_none_47fe850581cf6782.manifest
File versionNot applicable
File size3,883
Date (UTC)11-Nov-2015
Time (UTC)00:29
PlatformNot applicable

↑ Back to the top


Keywords: kbqfe, kbsurveynew, kbfix, kbexpertiseadvanced, kbautohotfix, kbhotfixserver, kb

↑ Back to the top

Article Info
Article ID : 3109093
Revision : 1
Created on : 1/7/2017
Published on : 12/9/2015
Exists online : False
Views : 205