The DFS Replication service crashes randomly in Windows Server 2008

The Distributed File System (DFS) Replication service crashes randomly on a computer that is running Windows Server 2008. Additionally, you experience the following symptoms:

• You may receive the following error message:
  Distributed File System Replication has stopped working
• The following event is logged in the Application log:

  Log Name: Application
  Source: Application Error
  Event ID: 1000
  Task Category: (100)
  Level: Error Keywords: Classic
  User: N/A
  Computer: <computer name>
  Description: Faulting application DFSRs.exe, version <file version>, time stamp <time stamp>, faulting module ntdll.dll, version <file version>, time stamp <time stamp>, exception code 0xc0000005, fault offset <offset>, process id <id>, application start time <time>.

• The following event is logged in the System log:

  Event ID: 7031
  Source: Service Control Manager
  Description: The DFS Replication service terminated unexpectedly
  The following corrective action will be taken in 60000 milliseconds: Restart the service.

This issue occurs because the DFS Replication service has some overlapped I/O requests. When a thread of an I/O request frees a related memory structure for a file, a second thread tries to access the freed memory structure. This behavior causes the DFS Replication service to crash.

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 Web site: 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, your computer must be running Windows Server 2008 Service Pack 2 (SP2). Additionally, the DFS Replication service under the File Server role must be installed.

For more information about how to obtain a Windows Server 2008 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

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 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 Server 2008 file information notes

• 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.
  Collapse this tableExpand this table

  Version	Product	SR_Level	Service branch
  6.0.600 1 . 22xxx	Windows Server 2008	SP1	LDR
  6.0.600 2 . 22xxx	Windows Server 2008	SP2	LDR

• Service Pack 1 is integrated into the release version of Windows Server 2008. Therefore, RTM milestone files apply only to Windows Vista. RTM milestone files have a 6.0.0000.xxxxxx version number.
• 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 SP2" section. MUM files and MANIFEST files, and the associated security catalog (.cat) files, are extremely important 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 Server 2008 SP2

For all supported x64-based versions of Windows Server 2008 SP2

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

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

Additional file information

Additional file information for Windows Server 2008 SP2

Additional files for all supported x86-based versions of Windows Server 2008 SP2

Additional files for all supported x64-based versions of Windows Server 2008 SP2