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64  Installation for Microsoft Exchange 2007 & 2010 Getting Started Guide
Screenshot 57 - Server roles detected and list of components to install.
7. A list of the Microsoft Exchange Server 2007/2010 server roles
detected and GFI MailEssentials components required is displayed.
Click Next to install the required GFI MailEssentials components.
8. Click Finish to finalize the installation.
The GFI MailEssentials installation is now complete and the anti-spam
system is up and running. For more information about how to optimize
GFI MailEssentials refer to Post-install actions chapter.
4.6 Installing on Microsoft Exchange Server 2007 clusters
On Microsoft Exchange 2007 servers only servers with the Mailbox
Role can be part of a cluster. Any other roles are required to be
installed on separate servers.
To install GFI MailEssentials as part of a Microsoft Exchange 2007
cluster, install GFI MailEssentials on a server running the Hub
Transport or the Edge Transport Role. Alternatively, you install GFI
MailEssentials on a separate machine in gateway/perimeter server
mode.
 On Microsoft Exchange 2007 server clusters without the Mailbox
role, the option to move SPAM to subfolders of the users‟ mailbox
is disabled.
 High availability for the Hub Transport, Edge Transport, Client
Access, and Unified Messaging server roles is achieved through a
combination of server redundancy, Network Load Balancing
(NLB), hardware load balancing, Domain Name System (DNS)
round robin, as well as proactive server, service, and infrastructure
management. In this case GFI MailEssentials will need to be
installed on all servers running the Hub Transport roles or all