The fax service intermittently crashes on a computer that is running Windows Server 2008 Service Pack 2 or Windows Server 2008 R2

Applies to: Windows Server 2008 Service Pack 2Windows Server 2008 R2

Symptoms


Consider the following scenario:
  • You install the Fax Server role on a computer that is running Windows Server 2008 Service Pack 2 (SP2) or Windows Server 2008 R2. 
  • You run an application or start a service to manage fax jobs on the computer.
In this scenario, the fax service (Fxssvc.exe) intermittently crashes. Additionally, the following event is logged in the Application log:

Cause


The issue occurs because of a race condition in the fax service. The fax service does not protect the fax job queue list in all cases. Therefore, a race condition may occur. When the race condition occurs, one thread removes a fax job while another thread tries to access the same fax job. Then, an access violation occurs and causes the fax service to crash. 

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: Note 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 Windows Server 2008 Service Pack 2 (SP2) or Windows Server 2008 R2 on which the Fax Server role is installed.

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.

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 Server 2008 file information notes
Important Windows Vista hotfixes and Windows Server 2008 hotfixes are included in the same packages. However, only "Windows Vista" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows Vista" 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.
    VersionProductSR_LevelService branch
    6.0.600
    2.
    22xxx
    Windows Vista and Windows Server 2008SP2LDR
  • 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" section. MUM files 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 Server 2008
File nameFile versionFile sizeDateTimePlatform
Fxsevent.dll6.0.6002.224697,68018-Aug-201016:56x86
Fxsmon.dll6.0.6002.2246939,42418-Aug-201016:56x86
Fxsroute.dll6.0.6002.2246967,58418-Aug-201016:56x86
Fxssvc.exe6.0.6002.22469523,77618-Aug-201015:17x86
Fxsunatd.exe6.0.6002.2246919,45618-Aug-201015:17x86
For all supported x64-based versions of Windows Server 2008
File nameFile versionFile sizeDateTimePlatform
Fxsevent.dll6.0.6002.224697,68018-Aug-201017:27x64
Fxsmon.dll6.0.6002.2246940,96018-Aug-201017:27x64
Fxsroute.dll6.0.6002.2246983,96818-Aug-201017:27x64
Fxssvc.exe6.0.6002.22469688,64018-Aug-201015:54x64
Fxsunatd.exe6.0.6002.2246916,89618-Aug-201015:54x64
Windows Server 2008 R2 file information notes
Important 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 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" 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 x64-based versions of Windows Server 2008 R2
File nameFile versionFile sizeDateTimePlatform
Fxsevent.dll6.1.7600.163857,68014-Jul-200901:27x64
Fxsmon.dll6.1.7600.1638541,47214-Jul-200901:40x64
Fxsroute.dll6.1.7600.1638582,94414-Jul-200901:40x64
Fxssvc.exe6.1.7600.20788689,15226-Aug-201005:49x64
Fxsunatd.exe6.1.7600.1638517,92014-Jul-200901:39x64

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 the Fax Server role, visit the following Microsoft website:
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 Server 2008

Additional files for all supported x86-based versions of Windows Server 2008
File nameUpdate.mum
File versionNot applicable
File size2,694
Date (UTC)18-Aug-2010
Time (UTC)22:25
PlatformNot applicable

File nameX86_3736252ad7c7dd2c6744091aacbd138e_31bf3856ad364e35_6.0.6002.22469_none_64cda9952c7dbc90.manifest
File versionNot applicable
File size699
Date (UTC)18-Aug-2010
Time (UTC)22:25
PlatformNot applicable

File nameX86_microsoft-windows-fax-service_31bf3856ad364e35_6.0.6002.22469_none_af5bd6e696b5dbfe.manifest
File versionNot applicable
File size53,748
Date (UTC)18-Aug-2010
Time (UTC)17:18
PlatformNot applicable
Additional files for all supported x64-based versions of Windows Server 2008
File nameAmd64_900c70bee3223283ec2ce261c8714eb2_31bf3856ad364e35_6.0.6002.22469_none_8d2a7e2d7a771627.manifest
File versionNot applicable
File size1,048
Date (UTC)18-Aug-2010
Time (UTC)22:25
PlatformNot applicable

File nameAmd64_microsoft-windows-fax-service_31bf3856ad364e35_6.0.6002.22469_none_0b7a726a4f134d34.manifest
File versionNot applicable
File size53,794
Date (UTC)18-Aug-2010
Time (UTC)17:50
PlatformNot applicable

File nameUpdate.mum
File versionNot applicable
File size2,714
Date (UTC)18-Aug-2010
Time (UTC)22:25
PlatformNot applicable

File nameWow64_microsoft-windows-fax-service_31bf3856ad364e35_6.0.6002.22469_none_15cf1cbc83740f2f.manifest
File versionNot applicable
File size39,881
Date (UTC)18-Aug-2010
Time (UTC)17:04
PlatformNot applicable

Additional file information for Windows 7 and for Windows Server 2008 R2

Additional files for all supported x64-based versions of Windows Server 2008 R2
File nameAmd64_2de5ee74d722124c54fa9f1b4ee4a885_31bf3856ad364e35_6.1.7600.20788_none_d31436d8f551e75e.manifest
File versionNot applicable
File size1,048
Date (UTC)26-Aug-2010
Time (UTC)15:22
PlatformNot applicable

File nameAmd64_microsoft-windows-fax-service_31bf3856ad364e35_6.1.7600.20788_none_09a52ebfb315565c.manifest
File versionNot applicable
File size50,125
Date (UTC)26-Aug-2010
Time (UTC)15:22
PlatformNot applicable

File nameUpdate.mum
File versionNot applicable
File size2,056
Date (UTC)26-Aug-2010
Time (UTC)15:22
PlatformNot applicable

File nameWow64_microsoft-windows-fax-service_31bf3856ad364e35_6.1.7600.20788_none_13f9d911e7761857.manifest
File versionNot applicable
File size22,666
Date (UTC)26-Aug-2010
Time (UTC)06:45
PlatformNot applicable