It is important to realize that Exchange 5.5 is a legacy system and should be upgraded to a newer version. Some support is available to connect to an Exchange 5.5 server in Microsoft Operations Manager (MOM) 2005, but it is unlikely that even this level of support continues in future versions of MOM. Once installed a server on the network that uses a new version of Exchange, one can still access a legacy Exchange 5.5 server through the Microsoft Transfer Agent (MTA) that provides routing functions that allow communication with Exchange 5.5. This allows having a hybrid environment, such as when temporarily keeping an older server, in case information may be needed until it is decommissioned. Although Exchange 5.5 is no longer supported by Microsoft, you can still acquire and import the Exchange 5.5 Management Pack for MOM 2000 or communicate with these servers in MOM 2005, using MTA. This provides some support to the legacy systems that may reside on the network.