Your access to network resources is slower in Windows XP than in earlier versions of Windows

Support for Windows XP has ended

Microsoft ended support for Windows XP on April 8, 2014. This change has affected your software updates and security options. Learn what this means for you and how to stay protected.

This article has been archived. It is offered "as is" and will no longer be updated.
On a Microsoft Windows XP-based computer, you may experience slower access to network resources than you experience on a Microsoft Windows 2000-based computer. For example, if you run a Microsoft Access database front-end program on a Windows XP-based computer, this program may access the back-end database slower than when the same Access program runs on a Windows 2000-based computer.
This problem occurs if the network-based files use the long file-name syntax instead of the 8.3 short file-name syntax. Specifically, the Windows XP Server Message Block (SMB) redirector component does not cache path information from long file names. In this scenario, Windows XP sends two SMB packets for every GetFileAttributes function call.

Service pack information

To resolve this problem, obtain the latest service pack for Windows XP. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
322389 How to obtain the latest Windows XP service pack

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.


You must have Windows XP Service Pack 1 installed to apply this hotfix. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
322389 How to obtain the latest Windows XP service pack

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 XP 32-bit editions
 Date           Time   Version        Size    File name -------------------------------------------------------------- 07-Jul-2004     02:25  5.1.2600.1547  92,160  Cscdll.dll 07-Jul-2004     02:15  5.1.2600.1551 426,112  Mrxsmb.sys 07-Jul-2004     02:15  5.1.2600.1547 166,016  Rdbss.sys
Windows XP 64-bit editions
Date         Time    Version          Size      File name---------------------------------------------------------------------------07-Jul-2004  03:29   5.1.2600.1547    237,056   Cscdll.dll IA-64     SP1QFE  07-Jul-2004  02:19   5.1.2600.1551  1,287,552   Mrxsmb.sys IA-64     SP1QFE  26-Jun-2004  13:48   5.1.2600.1547    495,616   Rdbss.sys IA-64      SP1QFE  07-Jul-2004  03:25   5.1.2600.1547     92,160   Wcscdll.dll x86       WOW 

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:
322756 How to back up and restore the registry in Windows
Important In addition to installing the above hotfix, you must add the following information to the registry to resolve this problem. To do so, use the following steps:
  1. Click Start, click Run, type Regedit in the Open box, and then click OK.
  2. Locate and click the following registry key:
  3. Click Edit, click New, and then click DWORD value.
  4. Type InfoCacheLevel to replace New Value #1, and then press ENTER.
  5. Click the InfoCacheLevel DWORD value in the right pane, click Edit, and then click Modify.
  6. Under Value data, select hexadecimal and type 10, and then click OK.
  7. Quit Registry Editor.

    Note InfoCacheLevel can have any of the following values in hexadecimal notation. The default value is 1.
    • 0 = Disables the caching for all files and folders
    • 1 = Enables the caching for files with short file name (8.3) - default value
    • 10 = Enables caching for all files
To work around this problem, use the 8.3 naming syntax to rename your networked files.
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: 834350 - Last Review: 12/08/2015 05:53:08 - Revision: 5.0

Microsoft Windows XP Professional, Microsoft Windows XP Professional x64 Edition

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