Other antivirus software (like Avira, Avast and Comodo) are keeping the configuration data in files (INIs and not only) that are located in the All Users\Application Data folder so the user can backup them and use them again in case of a new install or format instead of reconfiguring the program. Kaspersky even has this option built in the Settings menu, you can save and restore a configuration file that is encrypted and cannot be edited in case that's the Symantec's fear.
I took a look inside the registry and also found nothing.