Looking at the Exchange 2007 Product Guide (available for download by clicking here), or by looking at the overview at the Microsoft WebSite for the Exchange Server 2007 Editions and Client Access Licenses, you will see that one of the major changes compared to the differences between standard and enterprise versions in previous versions of Exchange, is the database size limit.
In Exchange 5.5, Exchange 2000, and Exchange 2003 up until sp1 the standard edition had a database size limit of 16 GB. With the release of Exchange 2003 Sp2, Microsoft increased the database size limit to 75GB! The database size limit for the enterprise edition has always been unlimited (or limited by hardware...)
Here's the table taken from the Microsoft Site detailing the differences between Standard and Enterprise Edition for Exchange 2007:
(c) http://www.microsoft.com/exchange/evaluation/editions.mspx
According to this table, the database size limit is unlimited for the standard edition. It was a great surprise for me to notice the following event log entry after installing a 32bit standard evaluation version of Exchange 2007:
What's going on?
The Exchange Server 2007 Standard Edition has apparantly a hard coded licensing database size limit of 50 GB, and for Service Pack 1 this is set to 250 GB...
Can this be changed?
Yes :-) the database size limit of 50 GB can be increased by creating the
Database Size Limit in Gb registry value.
How do you do this?
The following two pictures show you the entry you have to do in the registry to change this, and the third one shows you the result after dismounting and mounting the store again.
What's the source for this registry key?
http://technet.microsoft.com/en-us/library/aa997432.aspxIs it the same for the enterprise edition?I haven't had the opportunity yet to check this on a 64bit enterprise edition Exchange 2007 server, so I'm interested to know if it is the same for the enteprise edition... rumour has it though that it is ;-)
Conclusion?
Database size limit for Exchange Standard and Enterprise edition is
unlimited (just to be complete, the hard limit for both is 16000 GB. ESE currently has a maximum size of 16384 GB (2 billion pages * 8 kB pages), this is 16 TB)! But don't forget to add/change the registry!
- Ilse
