Just as an FYI, There should have been a backup of the file in the Archived Data folder as well, This folder should contain a rolling five (5) day backup of all config files in that Directory. This folder (Archived Data) will be present at the user level, domain level and system level and will be in the respective directories.
default locations
C:\Program Files (x86)\SmarterTools\SmarterMail\Service\Settings
C:\SmarterMail\Domains\domain_name\
C:\SmarterMail\Domains\domain_name\Users\user_name
Tony Scholz
System/Network Administrator
SmarterTools Inc.
www.smartertools.com