Applies to: Exchange Server 2007 SP3, Exchange Server 2007 SP2, Exchange Server 2007 SP1
Topic Last Modified: 2008-11-14

This topic describes the use of Windows Internet Name Service (WINS) together with Microsoft Exchange Server 2007. When Exchange 2007 is in a single domain, WINS is not required in the domain. However, in multidomain environments where Exchange 2007 is installed in one or more domains, WINS is required.

Client computers that are running Microsoft Outlook 2003 or an earlier version require NetBIOS name resolution and may require WINS.

WINS may also be required for client computers that are running Outlook 2007 Service Pack 1 (SP1) or an earlier version of Outlook. When your mailbox is migrated to a new Exchange server forest, Outlook 2007 cannot connect to a server in that forest. This issue occurs because Outlook 2007 uses the NetBIOS name for the server, instead of the fully qualified domain name (FQDN). This issue is corrected by a hotfix. For more information about this hotfix, see Microsoft Knowledge Base article 941275, Description of the Outlook 2007 post-Service Pack 1 hotfix package: January 28, 2008.

WINS in Multidomain Environments

WINS is required in multidomain environments when Exchange 2007 is installed in one or more domains. This is because WINS enables NetBIOS name resolution between computers on multiple subnets. NetBIOS names are also known as "short names." Short names are used for name resolution instead of fully qualified domain names (FQDN). For example, instead of using the FQDN ServerA.corp.CompanyName.com to locate a computer, you use the short name (ServerA).

However, when short names are used, computers cannot have the same name, even if they are in a different domain. For example, in a WINS environment, only one computer can be named ServerA. This differs from Domain Name System (DNS) name resolution where many computers can be named ServerA. For example, one computer can be named ServerA.EUROPE.DOMAIN.COM, and another computer can be named ServerA.AMERICA.DOMAIN.COM. If you are located in the AMERICA domain, and you type \\ ServerA, you connect to ServerA in the AMERICA domain. If you are located in the AMERICA domain, and you want to connect to ServerA in the EUROPE domain, you must specify ServerA.EUROPE.DOMAIN.COM as the FQDN. To use short names in multidomain environments, you must deploy WINS to make sure that duplicate names do not exist.