Mailbox Formats

Mailbox formats supported by Dovecot:

Name

Tag

Description

obox

obox

OX Dovecot Pro object storage mailbox format. (Pro only)

mbox

mbox

Traditional UNIX mailbox format. Users’ INBOX mailboxes are commonly stored in /var/spool/mail or /var/mail directory. Single file contains multiple messages.

Maildir

maildir

One file contains one message. A reliable choice since files are never modified and all operations are atomic. The top-level Maildir directory contains the Maildir/cur, Maildir/new, and Maildir/tmp subdirectories.

dbox

sdbox

single-dbox, one message per file.

Dovecot’s own high performance mailbox format. Messages are stored in one or more files, each containing one or more messages.

mdbox

multi-dbox, multiple messages per file.

imapc

imapc

Use remote IMAP server as mail storage.

pop3c

pop3c

Use remote POP3 server as mail storage.

The Tag column indicates the tag which is used at the beginning of a mailbox location specification.