Active Directory domain is mixed mode
[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at http://go.microsoft.com/fwlink/?linkid=34707.]
Topic Last Modified: 2006-08-10
Microsoft® Exchange Server 2007 setup cannot continue because an existing Active Directory domain is not set to Microsoft Windows®°2000 Server native mode or better.
Exchange 2007 setup will create Universal Security Groups that can only exist in Windows 2000 Server native mode, or better, domains.
To resolve this issue, follow these steps to raise the domain functional level to at least the Windows 2000 Server native level, and then rerun Exchange 2007 setup.
To raise the domain functional level
Open Active Directory Domains and Trusts.
In the console tree, right-click the domain for which you want to raise functionality, and then click Raise Domain Functional Level.
In Select an available domain functional level, use one of the following procedures:
To raise the domain functional level to Windows 2000 Server native, click Windows 2000 native, and then click Raise.
To raise domain functional level to Windows Server® 2003, click Windows Server 2003, and then click Raise.
If you have or will have any domain controllers running Windows NT® 4.0 and earlier, do not raise the domain functional level to Windows 2000 Server native. After the domain functional level is set to Windows 2000 Server native, it cannot be changed back to Windows 2000 Server mixed.
If you have or will have any domain controllers running Windows NT 4.0 and earlier or Windows 2000 Server, do not raise the domain functional level to Windows Server 2003. After the domain functional level is set to Windows Server 2003, it cannot be changed back to Windows 2000 Server mixed or Windows 2000 Server native.