DSAccess tuning values in the Instance0 registry subkey are deleted when you configure Directory Access to automatically discover the configuration domain controller in Exchange 2000 Server (830930)


The information in this article applies to:

  • Microsoft Exchange 2000 Server
Important This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

On your Microsoft Exchange 2000 Server, DSAccess cache tuning values that you manually configured in the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeDSAccess\Instance0 registry subkey no longer have any performance effect. When you try to view the registry subkey, you notice that the Instance0 subkey that held the tuning values no longer exists.

CAUSE

This problem occurs if you enable the Automatically discover servers option for Directory Access to automatically discover the configuration domain controller. When you enable the Automatically discover servers option for the configuration domain controller, the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeDSAccess\Instance0 registry subkey is unexpectedly deleted.

The ConfigDCHostName registry entry and the ConfigDCPortNumber registry entry in the Instance0 subkey are used to statically map the Configuration Domain Controller value. Instead of removing only the ConfigDCHostName and ConfigDCPortNumber registry entries as you expect, when the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeDSAccess\Instance0 registry subkey is deleted any manually entered DSAccess tuning values that you configured by using the Instance0 subkey are lost.

RESOLUTION

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Exchange 2000 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.
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. 
   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   21-Nov-2003  03:54  6.0.6539.0      4,370,432  Adcadmin.dll     
   21-Nov-2003  03:55  6.0.6539.0         69,632  Ccmproxy.dll     
   21-Nov-2003  03:55  6.0.6539.0      2,109,440  Cdoexm.dll       
   21-Nov-2003  03:54  6.0.6539.0      8,470,528  Exadmin.dll      
   21-Nov-2003  03:54  6.0.6539.0      3,850,240  Excluadm.dll     
   21-Nov-2003  03:55  6.0.6539.0      1,867,776  Exmgmt.exe       
   21-Nov-2003  03:41  6.0.6539.0        720,896  Exsp.dll         
   21-Nov-2003  03:55  6.0.6539.0      1,347,584  Exwmi.dll        
   21-Nov-2003  03:55  6.0.6539.0         73,728  Inproxy.dll      
   21-Nov-2003  03:55  6.0.6539.0      2,969,600  Mad.exe          
   21-Nov-2003  03:55  6.0.6539.0        811,008  Madmsg.dll       
   21-Nov-2003  03:54  6.0.6539.0      4,698,112  Maildsmx.dll     
   21-Nov-2003  03:55  6.0.6539.0         77,824  Pcproxy.dll      
   21-Nov-2003  03:55  6.0.6539.0         94,208  X400prox.dll
Note Because of file dependencies, this update requires Exchange 2000 Server Service Pack 3 (SP3). For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

301378 How to obtain the latest Exchange 2000 Server service pack

WORKAROUND

To work around this problem, back up the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeDSAccess\Instance0 subkey before you enable the Automatically discover servers option for Directory Access to automatically discover the configuration domain controller. After you enable the Automatically discover servers option, restore the registry subkey. To preserve the enabled Automatically discover servers setting, you must edit the registry file before you restore it. To do so, follow these steps.

Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
  1. Start Registry Editor. To do so:
    1. Click Start, and then click Run.
    2. In the Open box, type regedit, and then click OK.
  2. Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeDSAccess\Instance0

  3. On the Registry menu, click Export Registry File.
  4. Type a file name in the File name box, and then click Save.
  5. Right-click the registry file that you saved in step 4, and then click Edit.
  6. Remove the "ConfigDCPortNumber"=value and the "ConfigDCHostName"="hostname" lines.

    Note This step preserves the Automatically discover servers setting when you enable the setting in step 7. If you do not delete these two lines, the Automatically discover servers option will be disabled when you restore the registry subkey.
  7. Save the edited registry file.
  8. After you enable the Automatically discover servers option for the configuration domain controller, double-click the registry file that you saved in step 4, and then click Yes to restore the information to the registry.

STATUS

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

MORE INFORMATION

To locate the Automatically discover servers check box for the configuration domain controller, follow these steps:
  1. In Exchange System Manager, expand Servers, right-click your Exchange 2000 server name, and then click Properties.
  2. Click the Directory Access tab.
  3. In the Show list, click Configuration Domain Controller. The Automatically discover servers check box appears at the bottom of the Directory Access tab.
For additional information about DSAccess, click the following article numbers to view the articles in the Microsoft Knowledge Base:

246175 The role of DSAccess in Exchange 2000 Server

246281 Useful Windows 2000 Performance Monitor counters to analyze DSAccess behavior

For more information about DSAccess performance tuning, visit the following Microsoft Web site, and then click the Tuning Exchange 2000 Performance hyperlink:

http://www.microsoft.com/technet/treeview/default.asp?url=/technet/prodtechnol/exchange/exchange2000/reskit/resguide/c31optim.asp

For additional information about the standard terminology that is used in Microsoft software updates, 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

Modification Type:MinorLast Reviewed:10/3/2005
Keywords:kbHotfixServer kbQFE kbQFE kbfix kbExchange2000preSP4fix kbbug KB830930 kbAudITPRO
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