Cannot install Exchange 2007 roles after you prepare Active Directory for Exchange 2010

[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]  

Topic Last Modified: 2009-12-16

When you run Microsoft Exchange Server 2010 Setup /PrepareAD, the Microsoft Exchange Server Analyzer Tool queries the existing Active Directory topology to determine whether any Microsoft Exchange Server 2007 server roles exist. If Exchange 2007 server roles are not detected, you receive the following warning message:

Setup is going to prepare the organization for Exchange Server 2010 via 'Setup /PrepareAD' and no Exchange Server 2007 roles have been detected in this topology. After this operation, it will be impossible to install any Exchange Server 2007 roles.

Before deploying Exchange Server 2010, consider the following factors that may require you to deploy an Exchange 2007 server with all server roles installed prior to deploying Exchange 2007:

  • Third-party or in-house developed applications   Applications developed for Exchange 2003 may not be compatible with Exchange 2010, and thus need to be upgraded or replaced. You can maintain these applications and the associated user population on Exchange 2003; move to Exchange 2007; or replace the software with a compatible version for Exchange 2010.

  • Coexistence or migration requirements   If you plan on migrating mailboxes into your organization, you can either deploy Exchange 2007 and use the Microsoft Transporter Suite, or you can use a third-party coexistence or migration solution. To download the Microsoft Transporter Suite, go to Microsoft Transporter Suite at the Microsoft Download Center.

In addition, when evaluating the options for your organization, make sure you have considered the following questions:

  • Do you have a strategy in place to move the dependent applications to Exchange 2010 before Exchange 2003 reaches end of support? For more information, visit the Microsoft Support Lifecycle Web page (

  • Does your strategy require WebDAV and Web Services coexistence (Exchange 2007)?

  • Have you considered third-party products that support Exchange or other Microsoft technologies that will allow you to meet your coexistence or migration requirements?

  • What is your hardware lifecycle approach (continue to use as many existing 32-bit servers as possible versus buying new 64-bit servers)?

  • What is your plan for migration (migrate all servers as fast as possible versus migrating in a phased strategy)? Similarly, what is your timeline for the coexistence of different versions of Exchange?

If you decide that you need to deploy an Exchange 2007 server prior to deploying Exchange 2010, the deployment of a single Exchange 2007 with all server roles is sufficient to enable the deployment of future Exchange 2007 servers in the organization. To deploy the Exchange 2007 server into your Exchange 2003 organization, follow these steps:

  1. Run Exchange 2007 Setup /PrepareSchema.

  2. Run Exchange 2007 Setup /PrepareAD.

  3. Run Exchange 2007 Setup /PrepareDomain on all domains that contain recipients, Exchange 2003 servers, or global catalogs that could be used by an Exchange server.

  4. Install an Exchange 2007 server with all four server roles (Hub Transport, Client Access, Mailbox, and Unified Messaging).