Topic Last Modified: 2006-12-07

The Microsoft® Exchange Server Analyzer Tool displays this warning if it finds Simple Mail Transfer Protocol (SMTP)–based site links in the Active Directory® directory service.

Microsoft Exchange Server 2007 routing will ignore Active Directory sites connected by SMTP site links. If Exchange 2007 is installed in sites that are connected only by an SMTP site link, routing errors will occur.

To address this issue, replace the SMTP site links with IP-based site links.

For more information about Active Directory IP site links, see "Planning to Use Active Directory Sites for Routing Mail" (