Mac OS X Aerochive Data File Location

 ~/Library/Application Support/Aerochive/Aerochive.xml
 ~/Library/Preferences/com.softwareops.Aerochive.plist

The ~ means your user directory, the name with the house icon, that is in every finder window.

Note: If you are backing up data, you must also backup your keychain data files and restore then at the same time.
 ~/Library/Keychains

Windows Aerochive Data File Location

Windows 7

C:\Users\Administrator\AppData\Roaming\SoftwareOps\Aerochive
 or
C:\Users\\AppData\Roaming\SoftwareOps\Aerochive
or
C:\Users\\AppData\\SoftwareOps\Aerochive

If you have XP  I believe the directory is something like
C:\Users\\Application Data\\SoftwareOps\Aerochive

Note: If you don't have Windows set to show hidden files, you will not see the AppData directory or the Application Directory in XP.  You must set Windows to show hidden files here is how.  See the setting Show hidden files, folders and drives.

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