System performance is negatively affected when Ntbackup.exe writes to a destination .bkf file

Support for Windows Server 2003 ended on July 14, 2015

Microsoft ended support for Windows Server 2003 on July 14, 2015. This change has affected your software updates and security options. Learn what this means for you and how to stay protected.

When the Ntbackup.exe program uses buffered input/output (I/O) to write to a destination .bkf file, the cache manager and the memory manager in Microsoft Windows Server 2003 may handle a large volume of data at a high throughput rate. This process consumes valuable system resources and may affect system performance.
This problem may occur if you back up large files with the Ntbackup.exe program, and then the cache manager cannot flush data to the disk sufficiently fast.

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 have to 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 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 tool in Control Panel.
   Date         Time   Version       Size       File name     Platform   -------------------------------------------------------------------    13-Apr-2004  17:49  5.2.3790.162  1,171,968  Ntbackup.exe  x86    13-Apr-2004  03:52  5.2.3790.162  46,080     Ws03res.dll   x86    13-Apr-2004  17:12  5.2.3790.162  3,341,824  Ntbackup.exe  IA-64    13-Apr-2004  03:52  5.2.3790.162  45,568     Ws03res.dll   IA-64
After you install this hotfix, you can use the Ntbackup program at a command prompt with the /FU parameter to enable unbuffered writes to a destination disk in Ntbackup. For additional information about command line parameters that you can use with Ntbackup, click the following article number to view the article in the Microsoft Knowledge Base:
814583 How to use command line parameters with the Ntbackup command in Windows Server 2003
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
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

Article ID: 839272 - Last Review: 07/24/2007 19:26:52 - Revision: 2.12

Microsoft Windows Server 2003, Standard Edition (32-bit x86), Microsoft Windows Server 2003, Enterprise Edition (32-bit x86), Microsoft Windows Server 2003, Enterprise x64 Edition

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