Exchange Organization is in 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]  

Topic Last Modified: 2006-06-05

The Microsoft® Exchange Server Analyzer Tool queries the Exchange organization container to determine the mode of the Exchange organization. The Exchange Server Analyzer checks the value of msExchangeMixedMode attribute. If the value of the msExchangeMixedMode attribute is True, the Exchange Server Analyzer displays an error. The error message indicates that the Exchange organization is running in mixed mode. Microsoft Exchange Server 2007 can only be installed in an organization that is in native mode. Therefore, you must switch an organization that runs in mixed mode to native mode to prepare for an Exchange 2007 deployment.


An organization that runs in native mode can contain only Exchange 2000 servers or later versions.

To prepare for an Exchange 2007 deployment, you must convert the Exchange organization to native mode by following these steps:

  1. Remove or decommission any remaining Exchange 5.5 servers.

  2. In Exchange System Manager, open the properties of the Exchange organization object, and then switch to native mode.

For more information about how to convert an Exchange organization to native mode, see "How to Convert from Mixed Mode to Native Mode in Exchange" ( in the Exchange Server 2003 Deployment Guide.

For more information about mixed mode and native mode for Microsoft Exchange, see the following Microsoft Knowledge Base articles: