Not sure if this is the right fix? We've added this issue to our memory dump diagnostic which can confirm.

Symptoms

Remote procedure call (RPC) threads may stop responding on a computer that is running Windows 7 or Windows Server 2008 R2 under a heavy load. If this issue occurs in the Lsass.exe process, authentication failures and loss of connectivity may occur. For example, Microsoft Outlook clients may lose connectivity to a server that is running Microsoft Exchange Server.

Cause

The issue occurs because of an error in the Rpcrt4.dll module that causes an infinite loop for any RPC call that is in the cancellation state.

Resolution

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 the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.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, contact 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 be running one of the following operating systems:

  • Windows 7

  • Windows 7 Service Pack 1 (SP1)

  • Windows Server 2008 R2

  • 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 use the hotfix in this package, 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.

File information

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 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:

    Version

    Product

    Milestone

    Service branch

    6.1.760 0.21xxx

    Windows 7 and Windows Server 2008 R2

    RTM

    LDR

    6.1.760 1.21xxx

    Windows 7 and Windows Server 2008 R2

    SP1

    LDR

  • 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 Server 2008 R2 and for Windows 7" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely 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 7

File name

File version

File size

Date

Time

Platform

Rpcrt4.dll

6.1.7600.21079

652,800

29-Oct-2011

04:38

x86

Rpcrt4.dll

6.1.7601.21849

653,824

29-Oct-2011

06:21

x86

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

File name

File version

File size

Date

Time

Platform

Rpcrt4.dll

6.1.7600.21079

1,219,584

29-Oct-2011

05:37

x64

Rpcrt4.dll

6.1.7601.21849

1,219,584

29-Oct-2011

06:47

x64

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

File name

File version

File size

Date

Time

Platform

Rpcrt4.dll

6.1.7600.21079

2,589,184

29-Oct-2011

04:21

IA-64

Rpcrt4.dll

6.1.7601.21849

2,589,184

29-Oct-2011

04:17

IA-64

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 file information for Windows 7 and for Windows Server 2008 R2

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

File name

Update.mum

File version

Not Applicable

File size

2,773

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

X86_35883fac5a75427b5b85ba640ec5e654_31bf3856ad364e35_6.1.7601.21849_none_e790e64cf933a0b2.manifest

File version

Not Applicable

File size

697

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

X86_9d1e40cda00a5d95dd155784cab05b6e_31bf3856ad364e35_6.1.7600.21079_none_7a9708e0e4120f39.manifest

File version

Not Applicable

File size

697

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

X86_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7600.21079_none_b46944b9bf79f30a.manifest

File version

Not Applicable

File size

59,061

Date (UTC)

29-Oct-2011

Time (UTC)

05:08

File name

X86_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7601.21849_none_b6703b47bc87d508.manifest

File version

Not Applicable

File size

59,061

Date (UTC)

29-Oct-2011

Time (UTC)

07:25

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

File name

Amd64_07bad6fe791dc1fada3d4298b22dfadf_31bf3856ad364e35_6.1.7600.21079_none_c18822eadc10b86d.manifest

File version

Not Applicable

File size

701

Date (UTC)

29-Oct-2011

Time (UTC)

11:13

File name

Amd64_4467eb4651649c9209dfb21254979c26_31bf3856ad364e35_6.1.7601.21849_none_1a0d0087ccd897b8.manifest

File version

Not Applicable

File size

701

Date (UTC)

29-Oct-2011

Time (UTC)

11:13

File name

Amd64_ab93eceb25a037ccba940a633118c222_31bf3856ad364e35_6.1.7600.21079_none_d9f05c0c6c5972a4.manifest

File version

Not Applicable

File size

1,044

Date (UTC)

29-Oct-2011

Time (UTC)

11:13

File name

Amd64_c0311cc32d5edaea880ed0313f9db9ce_31bf3856ad364e35_6.1.7601.21849_none_7e497d3a292db5f8.manifest

File version

Not Applicable

File size

1,044

Date (UTC)

29-Oct-2011

Time (UTC)

11:13

File name

Amd64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7600.21079_none_1087e03d77d76440.manifest

File version

Not Applicable

File size

59,065

Date (UTC)

29-Oct-2011

Time (UTC)

06:14

File name

Amd64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7601.21849_none_128ed6cb74e5463e.manifest

File version

Not Applicable

File size

59,065

Date (UTC)

29-Oct-2011

Time (UTC)

08:28

File name

Update.mum

File version

Not Applicable

File size

3,215

Date (UTC)

29-Oct-2011

Time (UTC)

11:13

File name

Wow64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7600.21079_none_1adc8a8fac38263b.manifest

File version

Not Applicable

File size

59,071

Date (UTC)

29-Oct-2011

Time (UTC)

04:58

File name

Wow64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7601.21849_none_1ce3811da9460839.manifest

File version

Not Applicable

File size

59,071

Date (UTC)

29-Oct-2011

Time (UTC)

06:44

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

File name

Ia64_0b88b3b763112b0ad615a151c5cc5495_31bf3856ad364e35_6.1.7600.21079_none_27a85a8ca2067d89.manifest

File version

Not Applicable

File size

1,042

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

Ia64_9c7bed2f0d7868debb88bc3799ce0a13_31bf3856ad364e35_6.1.7601.21849_none_be8b8b979a5816c2.manifest

File version

Not Applicable

File size

1,042

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

Ia64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7600.21079_none_b46ae8afbf77fc06.manifest

File version

Not Applicable

File size

59,063

Date (UTC)

29-Oct-2011

Time (UTC)

06:01

File name

Ia64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7601.21849_none_b671df3dbc85de04.manifest

File version

Not Applicable

File size

59,063

Date (UTC)

29-Oct-2011

Time (UTC)

07:24

File name

Update.mum

File version

Not Applicable

File size

1,947

Date (UTC)

29-Oct-2011

Time (UTC)

11:12

File name

Wow64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7600.21079_none_1adc8a8fac38263b.manifest

File version

Not Applicable

File size

59,071

Date (UTC)

29-Oct-2011

Time (UTC)

04:58

File name

Wow64_microsoft-windows-rpc-local_31bf3856ad364e35_6.1.7601.21849_none_1ce3811da9460839.manifest

File version

Not Applicable

File size

59,071

Date (UTC)

29-Oct-2011

Time (UTC)

06:44

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