A memory leak condition occurs when you create a CDO program or a MAPI32 program to log on or log off many mailboxes in Exchange Server 2003 SP1

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When you create a program that uses Collaborative Data Objects (CDO) or MAPI32 to log on to or to log off mailboxes, you may experience a memory leak condition when you use this program to access many mailboxes in Microsoft Exchange Server 2003 Service Pack 1 (SP1).
This problem occurs if your CDO or MAPI program uses impersonation to access these Exchange 2003 SP1 mailboxes. This problem occurs because certain MAPI heap cleanup code is not enabled in Exchange Server 2003 SP1.

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 be running Exchange 2003 Service Pack 1 (SP1) to install this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
836993 How to obtain the latest service packs for Exchange Server 2003

Restart requirement

You do not 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--------------------------------------------------------------28-Jan-2005  03:13  6.5.7232.75       708,608  Cdo.dll        28-Jan-2005  03:12  6.5.7232.75       635,904  Mapi32.dll     

Hotfix installation information

Note The program that is using CDO or MAPI must be on the same computer as Exchange Server 2003. Otherwise, the memory leak may still occur.

This hotfix adds the following value to the Windows registry:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Messaging Subsystem\Applications

Value name: CleanUpMAPIHeap
Value type: REG_DWORD
Value data: 0 or 1
Note Set this registry value to "1" to enable the MAPI heap cleanup code.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more 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
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
817903 New naming schema for Exchange Server software update packages
XADM, MAPI, CDO, Leak, Impersonation, enumerate, messages, logon, logoff

Article ID: 891509 - Last Review: 10/27/2013 07:04:36 - Revision: 1.9

Microsoft Exchange Server 2003 Service Pack 1

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