When running the Exchange Server Pre-Deployment Analyser in preparation for an exchange migration it found a problem on the existing Exchange 2003 server.
Link state suppression in not enabled
Before introducing Exchange Server 2010 into this topology, the ‘SuppressStateChanges’ configuration parameter should be set to ‘1’ on server server.domain.local. This parameter is essential if you plan to create multiple connectors to the dedicated Exchange 2010 routing group.
It is a relatively simple fix to correct this error
Open Regedit
Go to HKLM\System\CurrentControlSet\Services\RESvc\ParametersRight click in the right hand windows select New, DWORD value and name it SuppressStateChanges
Double click on the new entry and change the value to 1
Close regedit and restart the following services
SMTP Service,
Microsoft Exchange Routing Engine,
and Microsoft Exchange MTA Stacks