hello to everyone and thanks for spent time in this We have an Win 2k3 sp2 and Exch 2k3 sp2 with an Event Id 12800 issue in one of the 5 Exchange 2003 servers. I already checked and appliedthe two support microsoft web pages: http://support.microsoft.com/kb/810371/and http://support.microsoft.com/?kbid=815372resulted of ExBPA. After that, I checked for VM Largest Block Size counter of the MSExchangeIS and Free System Page Table Entries under the memory counter range values appear OK. The events 9665 and 12800 still apperaring.After 6 days of rebooting, OWA stops responding and nobody can authenticate. After rebooting or restart de Information Store service, OWA functions normally but event 12800 still appers. The [operating systems] line of Boot.ini is above: multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003, Enterprise" /noexecute=optout /fastdetect /3GB /USERVA=3030 /BURNMEMORY=4096 Because this server has RAM of 8 GBWhat else can I do?

Hi, Exchange 2003 performs an optimal memory configuration check when the Store.exe process starts. If the memory settings are not optimal, an event ID 9665 warning message is logged to the application event log of Event Viewer. When virtual memory is heavily fragmented, message processing problems and message conversion problems may occur. Users may experience performance issues and may not be able to access their messages. Event 12800 will repeatedly occur in the application event log, where each occurrence is logged several seconds after the last occurrence, indicate extreme virtual memory fragmentation. When VM Largest Block Size is small (less than 10 MB),then event 12800 will be generated, please try to follow the below steps to trouble shoot this issue: 1. Please apply the latest update for Windows 2003 Server. 2. Set the /3GB switch in the Boot.ini file. 3. Minimize the number of storage groups on the server. 4. Set the HeapDeCommitFreeBlockThreshold DWORD value to 0x00040000 (in hexadecimal format) in the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager 5. Adjust the store database cache size. 6. Reduce the maximum number of ESE open tables. Detail steps you can refer to the below Knowledge base article: How to troubleshoot virtual memory fragmentation in Exchange Server 2003 and Exchange 2000 Server http://support.microsoft.com/kb/325044 Hope it helps. Xiu

Really thanks Xiu, These are the settings actually: 1. All hotfixes are installed in W2K3 SP2 System, 2. The /3GB is set please check its boot.ini content: [boot loader]timeout=30default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS[operating systems]multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003, Enterprise" /noexecute=optout /fastdetect /3GB /Userva=3030 /BURNMEMORY=4096 3. There are only 2 Storage Groups with 500 mailboxes and 4 Databases. 4. The HeapDeCommitFreeBlockThreshold was set 0x00040000 value. 5& 6. For 500 usersare necessary these settings (database cache size and number of ESE open tables)? The values for VM Largest Block Size are: Average: 901513216 MAximum: 901513216 What Can I do?

I'd remove the extra 4g of memory.. We tried the burn memory switch on our new Dell 6850s with 16g and still had memory issues.

You can use ADSI Edit to modify modify the value of the msExchESEParamCacheSizeMax attribute to adjust the store database cache size. By default, Exchange 2003 queries the memory configuration of the computer, and then uses up to 229376 pages (896 MB) if the /3GB switch is set on the server or 147456 pages (576 MB) if the /3GB switch is not set on the server. On a server that has more than 2 GB of memory, you may want to increase the size of the ESE buffer. However, if you do so, you may cause memory fragmentation because of the reduced address space that is available to the rest of the store functions. Microsoft recommends that you do not set this value higher than 311296 pages (1200 MB). To reduce the maximum number of open tables that is maintained by ESE, set the msExchESEParamMaxOpenTables attribute on each storage group object to 27600. To do so, follow these steps: a. Start ADSI Edit. Note ADSI Edit is included with the Windows 2000 Support Tools. To install the Windows 2000 Support Tools, right-click the Suptools.msi file in the Support\Tools folder of the Windows 2000 CD-ROM, and then click Install. b. Expand Configuration Container [ServerName.DomainName.com], expand CN=Configuration,DC=DomainName,DC=com, expand CN=Services, expand CN=Microsoft Exchange, expand CN=OrganizationName, expand CN=Administrative Groups, expand CN=Administrative Group (where Administrative Group is the administrative group that contains the storage group that you want to modify), expand CN=Servers, expand CN=ServerName, and then expand CN=InformationStore. c. Right-click CN=Storage Group (where Storage Group is the storage group that you want to modify), and then click Properties. d. In the Select which properties to view list, click Both. e. In the Select a property to view list, click msExchESEParamMaxOpenTables. f. In the Edit Attribute box, type 27600, and then click Set. g. Click Apply, click OK, and then quit ADSI Edit. More information please refer to the "How to optimize virtual memory usage" part from the below article: http://support.microsoft.com/kb/325044 Hope it helps. Xiu