This is a guide as to how to set up Outlook (Not Outlook Express or Windows Live Mail) for IMAP. Once you have tested these settings, don't forget to delete the old mail account from your computer. YOU SHOULD NOT MIX IMAP and POP3 on any e-mail account. Make sure you know exactly which edition of Outlook you are using.
Using the correct server name and port numbers is. Contact support if you're having trouble.