Backup and restore to Core disables voicemail

Finally upgraded my production physical box to latest modules as of today.
Then did the same to my warm spare.
Backed up the production box and restored all settings to the spare.
Restore seems to have worked perfectly except my extensions had their voicemail disabled. That initially gave a bad IVR destination warning. A quick trip to the extensions fixed it, but I have only two extensions with voicemail.