Dovecot can't access mailbox that exists (nested)

[Edgaras Lukoševičius]

Hello,

I have this strange situation on nested mailboxes (directories)


# dovecot --version
2.2.36 (1f10bfa63)


# doveconf -n

# 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.24 (124e06aa)
# OS: Linux 3.10.0-693.21.1.el7.x86_64 x86_64 CentOS Linux release 
7.5.1804 (Core)


mail_access_groups = vmail
mail_location = maildir:%h
mail_plugins = quota stats quota_clone
mailbox_list_index = yes
managesieve_sieve_capability = fileinto envelope encoded-character 
subaddress comparator-i;ascii-numeric relational regex imap4flags copy 
include variables body environment mailbox date index ihave duplicate 
mime foreverypart extracttext
namespace inbox {
   inbox = yes
   location =
   mailbox Drafts {
     auto = subscribe
     special_use = \Drafts
   }
   mailbox Junk {
     auto = subscribe
     special_use = \Junk
   }
   mailbox Sent {
     auto = subscribe
     special_use = \Sent
   }
   mailbox "Sent Messages" {
     special_use = \Sent
   }
   mailbox Trash {
     auto = subscribe
     special_use = \Trash
   }
   prefix = INBOX.
   separator = .
   type = private
}

protocols = imap lmtp pop3 sieve

service imap-login {
   inet_listener imap-dsync {
     port = 1143
   }
   inet_listener imap {
     port = 143
   }
   inet_listener imaps {
     port = 993
     ssl = yes
   }
   process_limit = 300
   process_min_avail = 1
}
service lmtp {
   inet_listener lmtp {
     port = 24
   }
   process_min_avail = 5
}
service managesieve-login {
   inet_listener sieve {
     port = 4190
     ssl = yes
   }
   process_min_avail = 5
}
service pop3-login {
   inet_listener pop3-dsync {
     port = 1110
   }
   inet_listener pop3 {
     port = 110
   }
   inet_listener pop3s {
     port = 995
     ssl = yes
   }
   process_limit = 300
   process_min_avail = 1
}

service stats {
   fifo_listener stats-mail {
     group = vmail
     mode = 0600
     user = vmail
   }
   fifo_listener stats-user {
     group = vmail
     mode = 0600
     user = vmail
   }
}
protocol lmtp {
   mail_plugins = quota stats quota_clone sieve
}
protocol imap {
   imap_client_workarounds = delay-newmail tb-extra-mailbox-sep
   mail_max_userip_connections = 50
   mail_plugins = quota stats quota_clone imap_quota imap_stats
}
protocol sieve {
   mail_max_userip_connections = 10
}
protocol pop3 {
   mail_plugins = quota stats quota_clone
   pop3_client_workarounds = outlook-no-nuls oe-ns-eoh
   pop3_enable_last = yes
}


# ls -1a (Mailbox structure)

cur
dovecot.index
dovecot.index.cache
dovecot.index.log
dovecot.list.index
dovecot.list.index.log
dovecot.mailbox.log
dovecot-uidlist
dovecot-uidvalidity
.Drafts
.Junk
maildirfolder
maildirsize
new
.Received 1.1522486 - Subdirname.Received
.Received 1.1522486 - Subdirname.Sent
.Sent
sieve
subscriptions
tmp
.Trash
.Trash.Sent (2)


# doveadm mailbox list -u name at domain.com
INBOX
INBOX.Trash
INBOX.Trash.Sent (2)
INBOX.Sent
INBOX.Received 1
INBOX.Received 1.1522486 - Subdirname
INBOX.Received 1.1522486 - Subdirname.Sent
INBOX.Received 1.1522486 - Subdirname.Received
INBOX.Junk
INBOX.Drafts


# doveadm mailbox status -u name at domain.com -t all INBOX.*
doveadm(name at domain.com): Error: Mailbox INBOX.Received 1: Failed to 
lookup mailbox status: Mailbox doesn't exist: INBOX.Received 1
doveadm(name at domain.com): Error: Mailbox INBOX.Received 1.1522486 - 
Subdirname: Failed to lookup mailbox status: Mailbox doesn't exist: 
INBOX.Received 1.1522486 - Subdirname
messages=16 recent=0 unseen=1 vsize=3432379


The problem is that it's not possible to move this mailbox between 
servers using dovecot dsync/imapc. But I can see the messages inside 
these mailboxes using external IMAP/POP clients.