XADM: Access Control List Upgrades Cause Slow Public Folder Performance; Fix Requires Exchange 2000 SP2

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Article ID: 328907 - View products that this article applies to.
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If you try to gain access to public folders on an Exchange 2000 server, you may experience a long delay when you try to expand the hierarchy of folders. During this delay, you may receive an RPC wait dialog box (depending on the version of Microsoft Outlook that you are using) that states the name of the server that contains the data that you are trying to access (which should be the Exchange 2000 public folder server).

This problem is most likely to occur in a mixed Microsoft Exchange Server version 5.5 and Exchange 2000 environment in which public folders are being migrated. In all cases, the clients point to Exchange 2000 public folder servers for hierarchy requests.


The access control list (ACL) must be upgraded when public folders and the public folder hierarchy object are migrated. That upgrade integrates the ACL with Microsoft Windows 2000 Active Directory. During the upgrade, the Exchange 2000 information store must contact a Windows 2000 domain controller to look up user accounts that are in the ACL list.

This problem may occur if the information store process makes too many calls to the domain controllers to obtain information. Other threads that are performing operations in the information store stop while they wait for such lookup calls to return. This creates a thread backlog and degrades performance.


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.

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, submit a request to 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. Component: Information store

The English version of this fix 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
   25-SEP-2002   16:34   6.0.5771.50      70,144   Ccmproxy.dll
   25-SEP-2002   18:06   6.0.5771.50     676,352   Davex.dll
   25-SEP-2002   18:03   6.0.5771.50     131,648   Drviis.dll
   25-SEP-2002   18:04   6.0.5771.50     578,116   Dsaccess.dll
   25-SEP-2002   16:16   6.0.5771.50     180,736   Dscmsg.dll
   25-SEP-2002   18:06   6.0.5771.50   2,208,256   Ese.dll
   25-SEP-2002   18:06   6.0.5771.50      41,472   Eseperf.dll
   25-SEP-2002   18:14   6.0.5771.50   3,518,976   Excdo.dll
   25-SEP-2002   18:03   6.0.5771.50      90,688   Eximap4.dll
   25-SEP-2002   16:07   6.0.5771.50     172,544   Exnntp.dll
   25-SEP-2002   18:06   6.0.5771.50   1,688,064   Exoledb.dll
   25-SEP-2002   18:03   6.0.5771.50      33,344   Expop3.dll
   25-SEP-2002   18:04   6.0.5771.50      33,344   Exproto.dll
   25-SEP-2002   18:06   6.0.5771.50     209,408   Exprox.dll
   25-SEP-2002   16:09   6.0.5771.50     135,680   Exres.dll
   25-SEP-2002   18:07   6.0.5771.50     295,424   Exsmtp.dll
   25-SEP-2002   16:18   6.0.5771.50     717,312   Exsp.dll
   25-SEP-2002   16:34   6.0.5771.50   1,339,904   Exwmi.dll
   25-SEP-2002   16:18   6.0.5771.50      41,472   Febecfg.dll
   25-SEP-2002   18:03   6.0.5771.50      33,340   Iisif.dll
   25-SEP-2002   18:04   6.0.5771.50     131,648   Iisproto.dll
   25-SEP-2002   18:04   6.0.5771.50      62,016   Imap4be.dll
   25-SEP-2002   16:21   6.0.5771.50     320,000   Imap4evt.dll
   25-SEP-2002   16:19   6.0.5771.50     127,488   Imap4fe.dll
   25-SEP-2002   18:03   6.0.5771.50     127,552   Imap4svc.dll
   25-SEP-2002   16:34   6.0.5771.50      74,240   Inproxy.dll
   25-SEP-2002   18:04   6.0.5771.50      41,532   Jcb.dll
   25-SEP-2002   18:54   6.0.5771.50     782,848   Madmsg.dll
   25-SEP-2002   16:32   6.0.5771.50   2,249,216   Mdbmsg.dll
   25-SEP-2002   16:09   6.0.5771.50      33,280   Mdbrole.dll
   25-SEP-2002   16:37   6.0.5771.50     897,536   Mdbsz.dll
   25-SEP-2002   16:16   6.0.5771.50      82,432   Msgtrack.dll
   25-SEP-2002   16:07   6.0.5771.50     147,968   Nntpex.dll
   25-SEP-2002   16:34   6.0.5771.50      78,336   Pcproxy.dll
   25-SEP-2002   18:02   6.0.5771.50     377,412   Phatcat.dll
   25-SEP-2002   18:03   6.0.5771.50      37,440   Pop3be.dll
   25-SEP-2002   16:21   6.0.5771.50     303,616   Pop3evt.dll
   25-SEP-2002   16:19   6.0.5771.50      25,088   Pop3fe.dll
   25-SEP-2002   18:02   6.0.5771.50      74,304   Pop3svc.dll
   25-SEP-2002   16:21   6.0.5771.50     164,352   Protomsg.dll
   25-SEP-2002   16:07   6.0.5771.50      66,048   Tokenm.dll
   25-SEP-2002   16:34   6.0.5771.50      94,720   X400prox.dll
   25-SEP-2002   16:34   6.0.5771.50   1,860,096   Exmgmt.exe
   25-SEP-2002   16:34   6.0.5771.50   2,949,632   Mad.exe
   25-SEP-2002   18:03   6.0.5771.50   4,551,232   Store.exe
NOTE: Because of file dependencies, this update requires Microsoft Exchange 2000 Server Service Pack 2 (SP2).


Microsoft has confirmed that this is a problem in Microsoft Exchange 2000 Server.


After you apply this fix, the information store creates a cache that contains the Microsoft Windows NT Security Identifier (SID) and indicates whether or not the SID is a user object or group object.

This cache is created and populated when a public folder is first touched. After the cache is populated, all calls to look up account SIDs are first directed to the information store cache. If the SID is not in the information store cache, the call is made to the domain controller, and then the information for that SID is added to the cache.

By default, the cache is maintained for one hour. If the cache exceeds the default 8 kilobytes (KB) of entries, older cache entries are removed to make room for the new entries.

You can use registry keys to adjust both the default cache time and the default cache size. Microsoft recommends that you do not change these default settings unless there you have evidence that doing so will increase performance.

To change the default SID cache expiry time (in milliseconds):
  1. Start Registry Editor (Regedt32.exe).
  2. Locate and then click the following key in the registry:
  3. On the Edit menu, click Add Value, and then add the following registry value:
    Value name: Lookup Sid Cache Expire
    Data type: REG_DWORD
    Radix: Hexadecimal
    Value data: The minimum value is 0x0. The maximum value is 0x5460 (six hours).
  4. Quit Registry Editor.
To change the default SID cache size (the number of items):
  1. Start Registry Editor (Regedt32.exe).
  2. Locate and then click the following key in the registry:
  3. On the Edit menu, click Add Value, and then add the following registry value:
    Value name: Lookup Sid Cache Size
    Data type: REG_DWORD
    Radix: Hexadecimal
    Value data: The minimum value is 0x400 (1,024 KB). The maximum value is 0x8000 (32,768 KB).
  4. Quit Registry Editor.


Article ID: 328907 - Last Review: October 26, 2013 - Revision: 4.5
  • Microsoft Exchange 2000 Server Service Pack 2
kbnosurvey kbarchive kbautohotfix kbhotfixserver kbqfe kbbug kbexchange2000presp4fix kbfix kbqfe KB328907

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