About the default or inherited archiving policy
A folder at the root level inherits the autoarchive policy set on Volume—Properties—Archiving and Purging. Autoarchive property settings you make for a folder and its contents become the default autoarchive settings for any subfolder and its contents.
By default:

The autoarchive policy for all file types and folders is Do not automatically delete this file and Do not archive file before deletion. If you run autoarchive without changing the policy for any item from the default policy, iHub deletes no file or folder on the Encyclopedia volume.

When you select Properties—Auto Archive for a folder, Management Console selects <Default> for File Type and Use the default/inherited policy from this document's file type. This folder and its contents inherit the autoarchive policy of the parent folder and its contents.

When you select Properties—Auto Archive for a file, Management Console selects Use the default/inherited policy from this file's file type. This file inherits the autoarchive policy that exists for a file of the same type in the parent folder.
When you select Properties—Auto Archive for multiple files or folders, Management Console does not select a policy setting, but Use the default/inherited policy from this file's file type functions the same as when you select Properties—Auto Archive for a single file. The selected files inherit the autoarchive policy for files of the same type in the parent folder.
About setting the autoarchive policy for multiple folders
You can set the autoarchive policy for multiple folders at the same time. The archive option values you choose for the selected folders will apply also to any item in a selected folder that inherits its archive policy from that selected folder.