[Robbie]

SYMPTOMS
The Microsoft Exchange 2000 Server message database (MDB) automatically shuts down and does not restart when it reaches the maximum size limit that is permitted. This behavior is by design to prevent the 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.

A new update to Exchange 2000 has been developed that permits you to temporarily increase the database size limit by 1 gigabyte. By increasing the size limit, you can selectively remove unnecessary database content, defragment the database, and reduce the database size to a manageable level that is below the defined limits for database size.

RESOLUTION
To resolve this issue, new functionality has been added to Exchange 2000 Standard Edition that allows an administrator to do the following: • 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, this functionality 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 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 on downloading and installing 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 planning to install the September 2003 Exchange 2000 Server Post-Service Pack 3 Rollup at a later time, 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 need it. This feature may receive additional testing. Therefore, if your system is not severely affected by the lack of this feature, Microsoft recommends 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 phone numbers and information about support costs, visit the following Microsoft Web site:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS
Prerequisites
Because of file dependencies, this update requires Microsoft 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
File Information
The English version of this update 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
--------------------------------------------------------------
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 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.

To add the registry entry to the Exchange 2000 computer, follow these steps:1. Click Start, click Run, and then type regedt32.exe.
2. Locate the following key in the registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\MSExchangeIS\<Exchange Server Name>\Private-<long hexadecimal string>
3. On the Edit menu, click Add Value, and then type the following in the Value name box: Temporary DB Size Limit Extension
4. Select REG_DWORD for the data type, and then click OK.
5. Enter a value of 1, and then click OK.
6. 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.
STATUS
This behavior is by design. However, the update that is described in this article modifies the designed behavior.

[rumen]

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