Symptoms

On a computer that is running Windows 7 or Windows Server 2008 R2, the Psxss.exe process frequently consumes 100 percent of the CPU's resources.

Cause

This problem occurs because a local procedure call (LPC) live lock occurs in the kernel.

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, go to 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 Service Pack 1 (SP1)

  • Windows Server 2008 R2 Service Pack 1 (SP1)

See Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2 for more information.

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 English (United States) 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, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.

    Version

    Product

    SR_Level

    Service branch

    6.1.760 1. 22xxx

    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 7 and Windows Server 2008 R2" 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

Appid-ppdlic.xrm-ms

Not applicable

3,013

06-May-2013

05:27

Not applicable

Appid.sys

6.1.7601.22318

50,176

06-May-2013

03:31

x86

Appidapi.dll

6.1.7601.22318

50,688

06-May-2013

05:01

x86

Appidcertstorecheck.exe

6.1.7601.22318

16,896

06-May-2013

03:30

x86

Appidpolicyconverter.exe

6.1.7601.22318

97,792

06-May-2013

03:31

x86

Appidsvc.dll

6.1.7601.22318

29,696

06-May-2013

03:30

x86

Csrsrv.dll

6.1.7601.22318

38,912

06-May-2013

05:02

x86

Ntkrnlpa.exe

6.1.7601.22318

3,972,968

06-May-2013

05:10

Not applicable

Ntoskrnl.exe

6.1.7601.22318

3,917,160

06-May-2013

05:10

Not applicable

Apisetschema.dll

6.1.7601.22318

6,656

06-May-2013

05:01

x86

Smss.exe

6.1.7601.22318

69,632

06-May-2013

03:02

x86

Apisetschema.dll

6.1.7601.22318

6,656

06-May-2013

05:01

x86

Smss.exe

6.1.7601.22318

69,632

06-May-2013

03:02

x86

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

File name

File version

File size

Date

Time

Platform

Appid-ppdlic.xrm-ms

Not applicable

3,013

06-May-2013

05:43

Not applicable

Appid.sys

6.1.7601.22318

61,440

06-May-2013

03:36

x64

Appidapi.dll

6.1.7601.22318

58,368

06-May-2013

05:17

x64

Appidcertstorecheck.exe

6.1.7601.22318

17,920

06-May-2013

03:36

x64

Appidpolicyconverter.exe

6.1.7601.22318

148,480

06-May-2013

03:37

x64

Appidsvc.dll

6.1.7601.22318

34,304

06-May-2013

05:17

x64

Csrsrv.dll

6.1.7601.22318

43,520

06-May-2013

05:17

x64

Ntoskrnl.exe

6.1.7601.22318

5,554,024

06-May-2013

05:26

x64

Apisetschema.dll

6.1.7601.22318

6,656

06-May-2013

05:17

x64

Smss.exe

6.1.7601.22318

112,640

06-May-2013

02:56

x64

Apisetschema.dll

6.1.7601.22318

6,656

06-May-2013

05:17

x64

Smss.exe

6.1.7601.22318

112,640

06-May-2013

02:56

x64

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

File name

File version

File size

Date

Time

Platform

Appid-ppdlic.xrm-ms

Not applicable

3,013

06-May-2013

04:46

Not applicable

Appid.sys

6.1.7601.22318

131,072

06-May-2013

03:07

IA-64

Appidapi.dll

6.1.7601.22318

116,736

06-May-2013

04:22

IA-64

Appidcertstorecheck.exe

6.1.7601.22318

39,424

06-May-2013

03:07

IA-64

Appidpolicyconverter.exe

6.1.7601.22318

282,624

06-May-2013

03:07

IA-64

Appidsvc.dll

6.1.7601.22318

74,240

06-May-2013

04:22

IA-64

Csrsrv.dll

6.1.7601.22318

94,720

06-May-2013

04:23

IA-64

Ntoskrnl.exe

6.1.7601.22318

11,125,608

06-May-2013

04:32

IA-64

Apisetschema.dll

6.1.7601.22318

6,656

06-May-2013

04:22

IA-64

Smss.exe

6.1.7601.22318

207,872

06-May-2013

02:25

IA-64

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 Microsoft uses to describe software updates.

Additional file information for Windows 7 and Windows Server 2008 R2

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

File name

X86_microsoft-windows-appid_31bf3856ad364e35_6.1.7601.22318_none_59e0fbb029838c63.manifest

File version

Not applicable

File size

15,313

Date (UTC)

06-May-2013

Time (UTC)

05:35

Platform

Not applicable

File name

X86_microsoft-windows-csrsrv_31bf3856ad364e35_6.1.7601.22318_none_cc1c226a1cb9e226.manifest

File version

Not applicable

File size

2,513

Date (UTC)

06-May-2013

Time (UTC)

05:42

Platform

Not applicable

File name

X86_microsoft-windows-os-kernel_31bf3856ad364e35_6.1.7601.22318_none_6ec54d052b7f52c5.manifest

File version

Not applicable

File size

16,151

Date (UTC)

06-May-2013

Time (UTC)

05:43

Platform

Not applicable

File name

X86_microsoft-windows-smss_31bf3856ad364e35_6.1.7601.22318_none_aecf9361908de017.manifest

File version

Not applicable

File size

26,386

Date (UTC)

06-May-2013

Time (UTC)

05:43

Platform

Not applicable

File name

X86_microsoft-windows-smss_31bf3856ad364e35_7.1.7601.22318_none_a0400fa71b7488e6.manifest

File version

Not applicable

File size

26,420

Date (UTC)

06-May-2013

Time (UTC)

05:40

Platform

Not applicable

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

File name

Amd64_microsoft-windows-appid_31bf3856ad364e35_6.1.7601.22318_none_b5ff9733e1e0fd99.manifest

File version

Not applicable

File size

15,317

Date (UTC)

06-May-2013

Time (UTC)

05:52

Platform

Not applicable

File name

Amd64_microsoft-windows-csrsrv_31bf3856ad364e35_6.1.7601.22318_none_283abdedd517535c.manifest

File version

Not applicable

File size

2,515

Date (UTC)

06-May-2013

Time (UTC)

05:56

Platform

Not applicable

File name

Amd64_microsoft-windows-os-kernel_31bf3856ad364e35_6.1.7601.22318_none_cae3e888e3dcc3fb.manifest

File version

Not applicable

File size

15,291

Date (UTC)

06-May-2013

Time (UTC)

05:58

Platform

Not applicable

File name

Amd64_microsoft-windows-smss_31bf3856ad364e35_6.1.7601.22318_none_0aee2ee548eb514d.manifest

File version

Not applicable

File size

26,679

Date (UTC)

06-May-2013

Time (UTC)

05:57

Platform

Not applicable

File name

Amd64_microsoft-windows-smss_31bf3856ad364e35_7.1.7601.22318_none_fc5eab2ad3d1fa1c.manifest

File version

Not applicable

File size

26,713

Date (UTC)

06-May-2013

Time (UTC)

05:52

Platform

Not applicable

File name

Wow64_microsoft-windows-appid_31bf3856ad364e35_6.1.7601.22318_none_c05441861641bf94.manifest

File version

Not applicable

File size

3,356

Date (UTC)

06-May-2013

Time (UTC)

05:19

Platform

Not applicable

File name

Wow64_microsoft-windows-csrsrv_31bf3856ad364e35_6.1.7601.22318_none_328f684009781557.manifest

File version

Not applicable

File size

1,136

Date (UTC)

06-May-2013

Time (UTC)

05:19

Platform

Not applicable

File name

Wow64_microsoft-windows-smss_31bf3856ad364e35_6.1.7601.22318_none_1542d9377d4c1348.manifest

File version

Not applicable

File size

8,429

Date (UTC)

06-May-2013

Time (UTC)

05:20

Platform

Not applicable

File name

Wow64_microsoft-windows-smss_31bf3856ad364e35_7.1.7601.22318_none_06b3557d0832bc17.manifest

File version

Not applicable

File size

8,429

Date (UTC)

06-May-2013

Time (UTC)

05:20

Platform

Not applicable

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

File name

Ia64_microsoft-windows-appid_31bf3856ad364e35_6.1.7601.22318_none_59e29fa62981955f.manifest

File version

Not applicable

File size

15,315

Date (UTC)

06-May-2013

Time (UTC)

05:24

Platform

Not applicable

File name

Ia64_microsoft-windows-csrsrv_31bf3856ad364e35_6.1.7601.22318_none_cc1dc6601cb7eb22.manifest

File version

Not applicable

File size

2,514

Date (UTC)

06-May-2013

Time (UTC)

05:27

Platform

Not applicable

File name

Ia64_microsoft-windows-os-kernel_31bf3856ad364e35_6.1.7601.22318_none_6ec6f0fb2b7d5bc1.manifest

File version

Not applicable

File size

15,289

Date (UTC)

06-May-2013

Time (UTC)

05:29

Platform

Not applicable

File name

Ia64_microsoft-windows-smss_31bf3856ad364e35_6.1.7601.22318_none_aed13757908be913.manifest

File version

Not applicable

File size

26,675

Date (UTC)

06-May-2013

Time (UTC)

05:28

Platform

Not applicable

File name

Wow64_microsoft-windows-appid_31bf3856ad364e35_6.1.7601.22318_none_c05441861641bf94.manifest

File version

Not applicable

File size

3,356

Date (UTC)

06-May-2013

Time (UTC)

05:19

Platform

Not applicable

File name

Wow64_microsoft-windows-csrsrv_31bf3856ad364e35_6.1.7601.22318_none_328f684009781557.manifest

File version

Not applicable

File size

1,136

Date (UTC)

06-May-2013

Time (UTC)

05:19

Platform

Not applicable

File name

Wow64_microsoft-windows-smss_31bf3856ad364e35_6.1.7601.22318_none_1542d9377d4c1348.manifest

File version

Not applicable

File size

8,429

Date (UTC)

06-May-2013

Time (UTC)

05:20

Platform

Not applicable

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