List all Outlook folder and subfolder with Applescript
Try this:

    tell application "Microsoft Outlook"
    set theAccount to the first exchange account whose name is "Exchange Account"
    set theInbox to inbox of theAccount
    set everyFolder to every folder of folder of container of theInbox
end tell


That will get you the sub folders of every folder. Hope that helps!

You can also specify the name of a folder

set theSubfolder to mail folder named "SubFolder Name"