When editing the host configuration of a scanner post 10.x install, you get an error stating that "New ethernet settings found to be invalid and cannot be saved for specified host. Old settings are retained." Changes to the host will not save.
The cause for this is bad or incorrect static routes in the host configuration. Symantec Messaging Gateway 10.x has built-in error checking with these static routes that will throw an error when encountered.
Remove or change the static routes to properly reflect the correct IP information for the network.