For Outlook 2007+
If you have created a new folder on the mail server using another application or a web browser and the new folder is not visible in the IMAP Folders dialog box, you can update the folder list using the following procedure:
In Mail view, right-click the top-level folder of the IMAP account in the navigation pane.
Click Update Mailing List.
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If the mail sent from an external mail client (outlook express, windows mail) does not appear in the mail centre interface when using IMAP protocol, try to set the following options in the IMAP tab of the account properties after creating an IMAP account:
Root folder path: leave blank
Check new messages in all folders: checked
Store special folders on the IMAP server: checked
Path to sent items: INBOX.Sent
Path to items: Drafts
Path to deleted items: Trash
Junk mail path: Spam
On the Options/Settings/Send tab, the Save a copy of sent messages to the Sent items folder checkbox must be checked.