Exchange 2000 16 Gig limits

Exchange 2000 is seems to be not working, event log is showing 9175 Mapi session errors .We followed below registery hack to get the Exchange databases to 17Gig. We will have to perform in-place upgrade after we complete the ESEUTIL. Event log 1221 shows not much of a claimable space. We will have to perform in place upgrade for exchange from Exchange 2000 to Exchange 2003, without upgrading to OS to windows 2003 and doing Exchange in-place upgrade, is breaking my heart (-:, management decision is overruling my desicion and my feelings one more time getting beat up my management desicion. Below is the registery hack to bump the databases up to 17Gig.

My proposed plan in this scenario is follow below

1. Identify the large mailboxes. ( located 5 mailbox close to 6Gig)
   
2. Requested Network administrator perform, local archive for those accounts
   
3. Applied register hack brought the server up and running ( I had to stop and restart several times, SMTP and MTA services along with Information store, finally changes took effect. Be patient if register may take little time to go in effect after the changes
   
4. Purge any mailbox, which has been deleted, run Cleanup agent
   
5. Finally run ESEUTIL /D , have enough coffee and rent good movie, to wait ESEUTIL to finish.
   

1. Click Start, click Run, and then type regedt32.exe.
2. Locate the following key in the registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\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.

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:

Best

Oz Ozugurlu