The Edge Transport role cannot be installed on the local computer
Topic Last Modified: 2007-01-03
Microsoft® Exchange Server 2007 setup cannot continue because its attempt to install the Edge Server role found other Microsoft Exchange roles already installed on this server.
Exchange 2007 setup cannot install the Edge Server role on a server that has other Microsoft Exchange roles installed.
The Microsoft Exchange Edge Server role is deployed in your organization's perimeter network and handles all Internet-facing mail flow. It provides the encryption and decryption of messages sent between trusted Microsoft Exchange organizations, and also protection against spam.
To resolve this issue, install the Edge Server role on a computer that does not have other Microsoft Exchange roles installed.