How to temporarily increase the Exchange 2000 16-gigabyte database size limit (813051)

CAUSE

This behavior is by design to prevent an Exchange Server 2000 Standard Edition Information Store database from trying to insert more data into the database file than it was designed to hold.

Frequently, you experience this behavior when you are running Microsoft Exchange 2000 Server Standard Edition. Exchange 2000 Server Standard Edition limits the database size to 16 gigabytes (GB).

Note The 16-GB size limit for the Exchange private mailbox store database and the 16-GB size limit for the Exchange public mailbox store database is the sum of the size of both the Priv.edb and the Priv.stm files. When you view the space that a mailbox uses in Exchange System Manager, the amount only includes the space that is used by the Priv.edb file. The amount does not include the space that the Priv.stm file uses.

When you put a limit on a mailbox, you only limit the storage in the Priv.edb file. You do not limit the storage in the Priv.stm file. For example, a mailbox may appear to use only 250 MB of space in Exchange System Manager. However, the total space that the mailbox uses may be 450 MB. This difference occurs because the 200 MB of space that the Priv.stm file uses does not appear in Exchange System Manager.

RESOLUTION

A new update to Exchange 2000 Server Standard Edition has been developed. This update lets you temporarily increase the database size limit by 1 GB.

To resolve this issue, the administrator must perform the following tasks:

Temporarily increase the database size limit by 1 GB.
Selectively remove unnecessary database content.
Defragment the database to reduce the database to a level that is in the defined boundaries of the database size.

In Exchange Server 2003, the functionality to temporarily increase the database size limit by 1 GB is built into the product. However, to enable this functionality, the administrator must create the new registry value that is mentioned in the following Knowledge Base article:

828070 Exchange Server 2003 mailbox store does not mount when the mailbox store database reaches the 16-GB limit

To resolve this issue in Exchange 2000, you can apply the September 2003 Exchange 2000 Server post-Service Pack 3 Rollup. Then the administrator must create the new registry value to enable this feature. For additional information about how to download and install the rollup, click the following article number to view the article in the Microsoft Knowledge Base:

824282 September 2003 Exchange 2000 Server post-Service Pack 3 Rollup

If you are plan to install the September 2003 Exchange 2000 Server post-Service Pack 3 Rollup later, but you require a fix for this issue now, read the following Update information" section.

Update Information

A supported feature that modifies the product's default behavior is now available from Microsoft, but it is only intended to modify the behavior that this article describes. Apply it only to systems that specifically require it. This feature may receive additional testing. Therefore, if the system is not severely affected by the lack of this feature, we recommend that you wait for the next Microsoft Exchange 2000 Server service pack that contains this feature.

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

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

Prerequisites

Because of file dependencies, this update requires Microsoft Exchange 2000 Server Service Pack 3 (SP3). For more 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

File Information

The English version of this update 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
--------------------------------------------------------------
17-Jan-2003  01:17  6.0.6401.0      3,915,776  Cdoex.dll        
17-Jan-2003  01:17  6.0.6401.0      3,567,616  Excdo.dll        
17-Jan-2003  00:32  6.0.6401.0        258,048  Exmime.dll       
17-Jan-2003  01:09  6.0.6401.0      1,691,648  Exoledb.dll      
16-Jan-2003  22:37  6.0.6401.0      2,265,088  Mdbmsg.dll       
16-Jan-2003  22:08  6.0.6401.0         32,768  Mdbrole.dll       
17-Jan-2003  00:31  6.0.6401.0      4,591,616  Store.exe

Create New Registry Value

The update requires you to create a new registry value to enable this feature.

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 your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To add the registry entry to the Exchange 2000 computer, follow these steps:

Click Start, click Run, and then type regedt32.exe.
Locate the following key in the registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\<Exchange Server Name>\Private-<long hexadecimal string>
On the Edit menu, click Add Value, and then type the following in the Value name box: Temporary DB Size Limit Extension
Select REG_DWORD for the data type, and then click OK.
Enter a value of 1, and then click OK.
Quit Registry Editor.

If the Temporary DB Size Limit Extension registry value exists for a specific database and if the value is set a value other than zero, the database size limit (if any) is increased by 1 gigabyte. However, this registry value is not read dynamically; it is only read when a database is started. When the Exchange Information Store starts, an event 9657 will be logged as a warning to inform you that you are using a temporary database size limit.

Note To prevent new e-mail content from being added to the mailbox store beyond the temporary 17-GB limit during the recovery process, we strongly recommend that you stop the Simple Mail Transfer Protocol (SMTP) service and the Microsoft Exchange MTA Stacks service before you mount the mailbox store. For more information about how to remove unnecessary database content and how to defragment the database, click the following article number to view the article in the Microsoft Knowledge Base: