VSS-based backup operations may fail if VSS tracing is enabled on a Windows Server 2003-based computer that has hotfix 940349 applied

Consider the following scenario:

• Hotfix 940349 is applied on a Windows Server 2003-based computer.
• Volume Shadow Copy Service (VSS) tracing is enabled on this computer.
• An application uses VSS to perform a backup operation.

In this scenario, the backup operation may not be completed successfully. Additionally, the following event is logged in the Application log:

Event Type: Error
Event Source: EventSystem
Event Category: (52)
Event ID: 4616
Date: Date
Time: Time
User: N/A
Computer: ComputerName
Description:
The COM+ Event System caught an access violation at address 0x77B74817 within method PostSnapshot of interface {F2B41165-A791-4C1F-9820-8BE45C784E32}. The method attempted to access address 0x00000D54.
msvcrt!wscanf + 0x15e2
msvcrt!_vsnwprintf + 0x30
VSSAPI! + 0x1c519
VSSAPI!VssFreeSnapshotProperties + 0x28c
VSSAPI!CVssJetWriter::Initialize(struct _GUID,unsigned short const *,bool,bool,unsigned short const *,unsigned short const *) + 0x2cdb2
VSSAPI!CVssJetWriter::Initialize(struct _GUID,unsigned short const *,bool,bool,unsigned short const *,unsigned short const *) + 0x2d4c5
VSSAPI!CVssJetWriter::Initialize(struct _GUID,unsigned short const *,bool,bool,unsigned short const *,unsigned short const *) + 0x2d882
VSSAPI!CVssJetWriter::Initialize(struct _GUID,unsigned short const *,bool,bool,unsigned short const *,unsigned short const *) + 0x2f881
ole32!ComPs_NdrDllGetClassObject + 0x6db
es! + 0xdf65
es! + 0xe5f1
es!DllRegisterServer + 0x7b03
es!DllRegisterServer + 0x7b28
es!ServiceMain + 0x77ce
es!ServiceMain + 0x795a
msvcrt!_endthreadex + 0xa3
kernel32!GetModuleFileNameA + 0xeb

This problem occurs because VSS incorrectly handles some arguments when the service is writing the VSS tracing log. Therefore, an access violation occurs.

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 2003 Service Pack 1 or Windows Server 2003 Service Pack 2 installed on the computer. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

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 2003 with Service Pack 1, x86-based versions

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

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

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

Windows Server 2003 with Service Pack 1, x64-based versions

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

Windows XP Professional x64 Edition with Service Pack 1

Windows XP Professional x64 Edition with Service Pack 2

To work around this problem, disable VSS tracing.

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

For more information about hotfix 940349, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to configure VSS tracing, click the following article number to view the article in the Microsoft Knowledge Base: For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: