I do:
Incoming/IMAP host/server: zimbra.snc.edu, TLS security, port 143
Outgoing/SMTP host/server: smtprelay.snc.edu, SSL security, port 465
Set up Outlook for IMAP access (use the "Incoming" information) to the
Zimbra. Synchronize your folders. Now you should be able to just "drag and
drop" email from the Zimbra account folders to local folders in Outlook. Be
sure you use the local folders, so they will be in the message store locally
on the computer. Once you are satisfied that your Zimbra account email is
available locally in MS Outlook, you can delete the Zimbra account from
Outlook.
The important point to grasp is that the IMAP account folders, which will
appear after you set up the account in Outlook, are not local, and will
disappear as soon as you remove the account from Outlook. So you will need
to copy their contents to local folders, which will not be in the folder
tree under the account.
