I just migrated my IMAP mailbox to ZCS by using Zimbra desktop. I had significantly less e-mail than you (bout 250megs), so this might not be the most sensible route for you.
1) Import all mail from your old account with the Zimbra Desktop Import wizard. It creates a tar.gz file in your desktop machine file system.
2) Remove the old IMAP account from Zimbra Desktop.
3) Create the new Zimbra account.
4) Export the imported tar.gz file to your new account. Oddly enough, there is no progress bar or any other feedback than ok/fail in this case.
In my case the old and new e-mail accounts had the same address. |