A Windows Server 2008-based computer that has a single-processor stops responding if an MPIO-connected device is repeatedly connected and then disconnected

Consider the following scenario:

• You are running a Windows Server 2008-based computer.
• The computer has a single processor installed.
• A device is connected to the computer through the Microsoft Multipath I/O (MPIO) path.
• A read or write operation is performed on the logical unit number (LUN) of the device.
• You repeatedly connect and then disconnect the MPIO path. For example, you repeatedly connect and then disconnect the cable to the device that is reliant on the MPIO path.

In this scenario, the computer stops responding.

This issue occurs because of a deadlock in the MultiService distributed service model.

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.

Prerequisites

To apply this hotfix, you must have Windows Server 2008 installed.

Restart requirement

You must restart the 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 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 2008, x86 version

Windows Server 2008, x64 version

Windows Server 2008, IA-64 version

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