Topic Last Modified: 2007-02-22

The Microsoft® Exchange Server Analyzer Tool queries the Active Directory® directory service to determine the name (cn) of each directory object with an object class of msExchExchangeServer. The cn value is a string that contains the short name of the Exchange Server computer. The Exchange Server Analyzer retrieves the cn, and then determines the length of the string. The length of the string is the number of characters in the Exchange server name. If the Exchange Server Analyzer determines that an Exchange server name exceeds 15 characters, an error is displayed.

Exchange Server 2007, Exchange Server 2003, and Exchange 2000 Server have several NetBIOS dependencies that may require you to use NetBIOS name resolution across different subnets for the successful operation of all Exchange components, depending on the network topology. The NetBIOS naming convention allows for 16 characters in a NetBIOS name. Microsoft, however, limits NetBIOS names to 15 characters and uses the 16th character as a NetBIOS suffix.

Because Exchange Server has NetBIOS dependencies, and because NetBIOS names cannot exceed 15 characters, server names exceeding 15 characters are not supported in an Exchange organization. Additionally, because of the widespread effects that renaming an Exchange Server computer can have throughout Active Directory and the Exchange organization, renaming an Exchange Server computer is not supported.

To correct this error

  1. Remove the incorrectly-named Exchange Server computer by using the Remove option.

  2. Rename the computer with a name that has 15 characters or fewer.

  3. Reinstall Exchange Server on the computer.

For information about removing Exchange Server 2007, see "How to Completely Remove Exchange 2007 from a Server" ( in the Microsoft Exchange Server 2007 Deployment documentation.

For information about removing Exchange Server 2003, see "How to Uninstall Exchange Server 2003," in the Exchange Server 2003 Deployment Guide (

For more information, see the following Microsoft Knowledge Base articles: