Use the Autocompletion Folders tabbed
section to specify contact folders to search when
Email and Calendar attempts to autocomplete addresses in the To, Cc, and Bcc fields of your messages.
To specify an address autocompletion folder, click on the Add button. Select the folder that you want from the Add a Folder dialog, then click OK.
To remove a folder from the list of address autocompletion folders, select the folder in the Extra Completion folders list, then click on the Remove button.