A NULL IP address is assigned to the network adapter in a Windows Server 2003-based computer


In some scenarios, a network adapter in a Microsoft Windows Server 2003-based computer that has been assigned a valid static IP address may be assigned a NULL IP address (


This problem occurs because of a race condition in TCP/IP.

Specifically, this problem may occur if both of the following conditions are true:
  • TCP/IP initializes faster than the network becomes ready.
  • Another component programmatically disables the Media Sensing feature in Windows Server 2003.
For example, Cluster Services (Clusnet.sys) may disable Media Sensing. User-mode applications may also disable Media Sensing by calling the IP Helper DisableMediaSense function.

This problem may also occur if you are using a Gigabit network adapter, because this network adapter may take longer to negotiate with the switch. This problem is even more likely to occur if multiple network adapters are tied together by a load-balancing failover NDIS MUX driver. In this scenario, the speed of the network initialization process may decrease significantly.


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 this specific problem. 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.


No prerequisites are required.

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later) 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 tool in Control Panel.

Windows Server 2003 32-bit editions

Date Time Version Size File name
13-Apr-2004 22:37 5.2.3790.163 334,336 Tcpip.sys
12-Apr-2004 22:56 271 Branches.inf
13-Apr-2004 23:51 9,766 Kb840711.cat
13-Apr-2004 23:45 354 Updatebr.inf
13-Apr-2004 23:45 5,694 Update_rtmqfe.inf

Windows Server 2003 64-Bit Edition

Date Time Version Size File name
13-Apr-2004 22:37 5.2.3790.163 971,776 Tcpip.sys
12-Apr-2004 22:56 271 Branches.inf
13-Apr-2004 23:51 9,766 Kb840711.cat
13-Apr-2004 23:47 354 Updatebr.inf
13-Apr-2004 23:47 5,714 Update_rtmqfe.inf


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

More Information

For additional information, 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, regarding the performance or reliability of these products.