This is a follow-up to an earlier post: Single-label Domain Names and Exchange Server 2007 SP1. Please refer to it for background information on this issue.
After investigating Exchange 2007 Service Pack 1 installed in an Active Directory domain with a Single-label Domain (SLD) name, Microsoft has changed the Setup prerequisite rule for SLDs from an Error to a Warning, thereby allowing Service Pack 1 installation to continue in SLD environments.
There are a few items that I want to point out:
- Not a recommended configuration
While Exchange 2007 SP1 is supported with SLDs, the Exchange product team's view is that SLDs are not a recommended configuration. While we will allow installation of Exchange 2007 SP1 in an SLD, we strongly recommend that you take step to move your organization out of this configuration.
- Not fully tested
Exchange 2007 and Exchange 2007 SP1 have not been fully tested in SLDs. The Exchange team investigated known issues and determined that there were sufficient workarounds to safely allow installation of SP1 to continue; however, there may be unknown issues that could arise from operating Exchange 2007 in an SLD environment.
- Deprecated in the next version of Exchange
The next version of Exchange will not support Active Directory domains with single-label domain names. Similarly, upgrades of Exchange servers currently deployed in single-label domains will not be supported. In this case, "next version" means the next major release of Exchange Server. Customers that intend to deploy the next version of Exchange must use fully qualified domain names.
- Documentation being updated
Currently, the existing TechNet documentation states that SLDs are not supported in Exchange 2007. We are working to change the documentation to reflect that SLDs are supported but not recommended configurations. The updated documentation is expected to be published on TechNet as part of the March 2008 document refresh in early March.
- Exchange 2007 does not support Domain Rename, and there are currently no plans for a Domain Rename Fixup Tool for Exchange 2007
The possibility of creating a domain rename fixup tool for Exchange 2007, similar to the one that was written for Exchange 2003, was discussed internally. The decision is that there will not be a similar tool written for Exchange 2007. The Domain Rename Fixup tool written for Exchange 2003 is not compatible with Exchange 2007, and should not be used in Exchange 2007 environments.
Read more at source: http://msexchangeteam.com/archive/2008/02/15/448140.aspx