IMAP (Internet Message Access Protocol) is used to access e-mails on a server, like POP, except that instead of being deleted, the messages remain on the servers. IMAP also allows the creation, renaming and deletion of server-side folders and the movement of messages from one folder to another. Most major mail clients offer support for the IMAP protocol. Except for very specific situations, it is recommended over POP3 because it is generally more efficient and it uses a more reliable storage format.
Since recently, mailboxes created from the command-line csoftadm interface are IMAP-accessible by default. With the web interface, the format is selectable at mailbox creation time.
If you do not have existing mailboxes in POP format that you wish to convert, you may skip the next two sections.
To make POP3-only mailboxes IMAP-accessible, issue the following csoftadm command:
csoftadm> mail mbox maildir mailbox-name
If you are using the web interface, bring up the mailbox setting page by clicking on the mailbox name, and select the new format.
To convert the mailbox located immediately under your home directory IMAP-accessible, issue the following shell command:
$ maildirmake ~/MaildirThen update all your aliases to point to "./Maildir/" (with the trailing slash), instead of "./Mailbox". Use the mbox2maildir(1) utility if you need to convert the contents of an existing mailbox file.
You can create/delete IMAP folders and move messages between them using your mail client. It is also possible to perform these operations using csoftadm's web interface. There are also several "webmail" programs which implement this feature.
Configure your mail client to connect to your assigned mail server address, and make sure to specify the IMAP protocol. You can use secure IMAP (IMAPS) if your client supports it. Alternatively, if you already have a ssh tunnel set up, you can use regular IMAP over it.