Exchange 2003 can detect link state changes, notify other Exchange servers about the changes, and advise them to use other routes. A minor state change is when a link is detected as either available or unavailable. The notification actually sends the entire state table. A major state change is an administrator-made manual routing change, such as adding a new connector or changing an existing connector’s attributes.
Sometimes, minor state change notifications are undesirable, such as when the notification sending of the entire state table could flood a network. This could happen in a large Exchange environment. It could also happen in a combined Exchange Server 2007and Exchange 2003 environment with multiple routing group connectors between routing groups and different Exchange 2003 bridgeheads in different routing groups.
To disable minor link state changes, use the following commands on each Exchange 2003 server:
1. Start the registry editor (regedit.exe).
2. Navigate to HKEY_LOCAL_MACHINESystemCurrentControlSetServicesRESvcParameters.
3. From the Edit menu, select New – DWORD value.
4. Enter as a name SuppressStateChanges and press Enter.
5. Double click the new value and set the value to 1, then click OK.
6. Close the registry editor and restart the SMTP, Microsoft Exchange Routing Engine, and the Microsoft Exchange MTA Stacks services.