Exchange database size limit
From TSG Library of Knowledge
Problem: Exchange 2003 has a hard limit of 18GB for data stores. If your data store's database reaches 18GB, it will be taken offline and cannot be put back online with removing the .log files from MDBDATA.
Solution: If you are using Exchange 2003 SP2 or later, you can edit the following registry entry to change the limit to up to 75GB:
- On the Exchange server, go to Start, Run, and type regedit.
- Browse to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\{SERVERNAME}\{DATABASE NAME} (where SERVERNAME is the your server's name and DATABASE NAME is your data store's name).
- Inside the data store's folder, create a new DWORD key called "Database Size Limit in Gb".
- Choose Decimal and type a number between 1 and 75 to choose the new limit of your database in gigabytes.
- Restart the Microsoft Exchange Information Store (or just restart the server).
- To confirm that the change has taken place, you can check your Application Log for messages from msexchangeis (Event ID #1216), which will include the current limit.
