Windows Server 2008 SP2-based computer freezes or crashes when the computer has Kaspersky Anti-Virus installed

Applies to: Windows Server 2008 Service Pack 2Windows Server 2008 EnterpriseWindows Server 2008 Enterprise without Hyper-V


When you have Kaspersky Anti-Virus installed on a computer that is running Windows Server 2008 SP2, you may experience one of the following issues:
  • Kaspersky Anti-Virus crashes.
  • The computer freezes.
  • The computer crashes.


This issue occurs when an IFS minifilter performs an instance redirection by changing the target instance pointer and marking the callback data dirty flag. This behavior may collapse the main functionality of the IFS minifilter, causing the system to freeze or 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 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.


To apply this hotfix, you must be running Windows Server 2008 SP2.

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:

968849 How to obtain the latest service pack for Windows Server 2008

Registry information

To apply this hotfix, 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.


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

More Information

When the Fltmgr!FltpPerformPreCallbacks routine detects that the target instance is changed incorrectly, the routine releases the OperationRundownRef instance in the new target instance. However, the routine does not release the rundown reference in the old (changed) instance at the same time. Therefore, the Fltmgr!FltpDrainPendingCallbacksForInstance routine freezes when the instance is torn down.

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

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.