There are few posts that I have seen related to the Exchange 2007 SP3 upgrade. Thought of sharing few information related to the schema upgrade part of Exchange 2007 SP3.
When you install Exchange 2007 SP3 it updates the Active Directory schema. The schema extension is basically to enable co-existence with Exchange 2010.
Before you install Exchange 2003 SP3, please verify few things mentioned below,
The machine on which you run the Exchange 2007 setup schema extension process must be:
- Windows Server 2003 SP2 with Windows Installer 4.5 installed
- Windows Server 2008 with Windows Installer 4.5 installed
- Windows Server 2008 SP2
The Preparing Schema and Active Directory will be automatically taken care by Service pack setup. You can use the following order in your organization.
- CAS Server
- Unified Messaging Server
- HUB Server
- Edge Transport server
- Mailbox server
More importantly, install the rollup soon after the SP3(Update Rollup 1 for Exchange Server 2007 Service Pack 3), because MS identified and fixed few SP3 issues in rollup(http://msexchangeteam.com/archive/2010/09/09/456198.aspx).