WINS servers on a network send multicast packets too frequently, and this generates excessive CPU usage and network broadcast storms in a Windows Server 2003 environment

Consider the following scenario:

• Windows Internet Name Service (WINS) is installed on a Windows Server 2003-based computer.
• Security update 961064 is installed on this WINS server. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
  961064 MS09-008: Description of the security update for WINS server: March 10, 2009

In this scenario, the CPU usage of all WINS servers on the same multicast network becomes excessive (50 to 100 percent of system resources). Specifically, the other WINS servers on the same multicast network are forced to receive and process many multicast packets from the problematic WINS server. The large volume of network traffic that is generated by this behavior means that users encounter poor network performance.

Additional investigation indicates that WINS sends multicast packets as fast as it can to IP address 224.0.1.24 on port 42.

This problem occurs because of a race condition on the WINS server.

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, Windows Server 2003 Service Pack 1 (SP1) or Windows Server 2003 SP2 must be installed on the WINS server.

Restart requirement

You 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 English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Windows Server 2003 with Service Pack 1, x86-based versions

Windows Server 2003, x64-based versions

Windows Server 2003 with Service Pack 1, Itanium-based versions

Windows Server 2003 with Service Pack 2, x86-based versions

Windows Server 2003 with Service Pack 2, x64-based versions

Windows Server 2003 with Service Pack 2, Itanium-based versions

You can restart WINS on the problematic server to work around the issue. However, the issue may occur again if the value of the following registry subkey is changed:

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: