Click the Get Folder List button.
Depending upon how many PST files you have added to your Outlook configuration, you will see a dialog box similar to what is displayed below:
Each top-level Folder represents a data store (or PST file). In the example above, we have three data stores from which to choose (Archive Folders, My Work Files, and Personal Folders).
Select one of the displayed data stores by clicking on its name. Do not select one of the sub-folders (such as Inbox, Sent Items, or Deleted Items) from the list.
All of your Folders - the location in which your email and attachments are stored - will be displayed by OAR in the PST Folder List, on the left side of your screen, after you click OK.