Microsoft KB Archive/834315

= CPU usage by the Exchange System Attendant service on offline address list servers in a hosting environment increases to 50 percent =

Article ID: 834315

Article Last Modified on 10/25/2007

-

APPLIES TO


 * Microsoft Exchange Server 2003 Enterprise Edition
 * Microsoft Exchange Server 2003 Standard Edition

-



Important This article contains information about how to modify the registry. Make sure that you back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows registry



SYMPTOMS
In a hosting environment where Microsoft Exchange Server 2003 computers are configured as offline address list servers, you may find that CPU usage by the Microsoft Exchange System Attendant service (Mad.exe) on each of the servers increases to 50 percent. You experience these symptoms even after you restart each server.

For example, you may experience these symptoms in a hosting environment where you have 10,000 offline address lists and 10 Exchange Server 2003 computers that are configured as offline address list servers.



CAUSE
This problem occurs in hosting environments where Exchange Server 2003 computers are configured as dedicated offline address list servers. This problem occurs in this type of hosting environment when the update schedule for offline address lists is set to Never run. The Microsoft Exchange System Attendant service uses an OABScan task to scan offline address lists that are generated on the server. This task is scheduled to run every 13 minutes and may increase CPU usage in the Microsoft Exchange System Attendant service to 50 percent. In a hosting environment that has this configuration, the OABScan task is not required.



Service pack information
To resolve this problem, obtain the latest service pack for Exchange Server 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

836993 How to obtain the latest updates and service packs for Exchange Server 2003

Hotfix information
A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Exchange Server 2003 service pack that contains this hotfix.

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

http://support.microsoft.com/contactus/?ws=support

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.

Component: Exchange System Attendant

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 item in Control Panel.

 Date         Time   Version       Size       File name -- 20-Dec-2003  04:35  6.5.6980.58   8,765,440  Mad.exe

Note Because of file dependencies, this hotfix requires Exchange Server 2003.



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section. This problem was first corrected in Exchange Server 2003 Service Pack 1.



MORE INFORMATION
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

After you apply the hotfix that is described in this article, you must edit the registry to activate the hotfix and to turn off the OABScan task. To do so, follow these steps:  Click Start, and then click Run. In the Open box, type regedit, and then click OK. Locate and then click the following registry subkey:

 On the Edit menu, point to New, and then click DWORD Value. Type Disable OABScanTask, and then press ENTER.</li> Right-click the Disable OABScanTask registry value that you created in step 5, and then click Modify.</li> In the Value data box, type 1, and then click OK.</li> Quit Registry Editor.</li></ol>

Note When you set the  registry value to 1, you turn off the OABScan task. If you want to turn on the OABScan task, set the  registry value to 0 (zero) or remove the   registry value. After you do so, the following event is logged in the application event log to notify you that the task started: Type: Information

Source: MSEXchangeSA

Category: General

Event ID: 9008

Description:

Microsoft Exchange System Attendant is starting 'Oabgen.dll'.

Keywords: kbqfe kbhotfixserver kbexchange2003sp1fix kbexchange2003presp1fix kbfix kbbug KB834315

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.