Some snapshots are not mounted in Windows Server 2003 SP2 after computer restarts if there are many snapshots

Consider the following scenario:

• You have a computer that is running Windows Server 2003 Service Pack 2 (SP2).
• There are many snapshots that are stored on the computer. For example, assume that there are 3,000 snapshots.

In this scenario, some snapshots are not mounted after this computer restarts. At the same time, the following event is logged in the System log: For example, assume that you use a System Center Data Protection Manager (DPM) server to manage thousands of snapshots on a computer that is running Windows Server 2003 SP2.

Note System Center Data Protection Manager (DPM) supports a maximum of 9000 snapshots for each DPM server.

In this scenario, only several hundred snapshots are mounted after the computer is restarted because of this issue. Additionally, DPM incorrectly reports that the related volumes have no free disk space when DPM cannot mount snapshots on these volumes.

This issue occurs because there is a 20-minute limitation for the snapshot detection phase.

The snapshot detection phase is slower on Windows Server 2003 than on later versions of Windows, and snapshot detection at startup time may take longer than the default time-out of 20 minutes. When the time-out occurs on a DPM replica volume, the mount of the associated recovery point volume cannot occur.

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 2003 Service Pack 2 (SP2). For more information about how to obtain a Windows Server 2003 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

Installation instruction

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: After you install this hotfix, a new registry key is created. This registry key is used to adjust the time limit for the snapshot detection phase. To resolve this issue, change the value of the following registry key:Note By default, the value for the registry key is the 20 decimal value that is equal to the 0x14 hexadecimal value. If the value of the registry key is less than the 20 decimal value, the computer ignores the registry key and uses the default time of 20 minutes for the snapshot detection phase.

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 2003 file information notes

• In addition to the files that are listed in these tables, this hotfix also installs an associated security catalog file (KBnumber.cat) that is signed with a Microsoft digital signature.

For all supported x86-based versions of Windows Server 2003 SP2

For all supported x64-based versions of Windows Server 2003 SP2

For all supported IA-64-based versions of Windows Server 2003 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: