Configure dovecot imap server

Dovecot is IMAP and POP3 server, install with:

pacman -Sy dovecot

NOTE: This page is for the Maildir in the home directory and is for plain no ssl login and for the system user:
create the Maildir folders:

sudo maildirmake.dovecot /home/mailuser/Maildir
sudo chown -R mailuser:mailuser /home/mailuser/Maildir

Just copy these files to thier folders and restart the dovecot service:

systemctl restart dovecot

And test the dovecot imap with telnet.
create /etc/dovecot/conf.d/10-ssl.conf

ssl = no

Configure the /etc/dovecot/conf.d/10-master.conf for exim server:

# Dovecot master configuration

# IMAP login service
service imap-login {
  inet_listener imap {
    port = 143
  }

  inet_listener imaps {
    port = 0
  }
}

service pop3-login {
  inet_listener pop3 {
  port = 110
  }
}
# IMAP service
#service imap {
#}

# Authentication service
service auth {
  # Socket for Dovecot processes (IMAP, doveadm)
  unix_listener auth-userdb {
    mode = 0666
    user = exim
    group = mail
  }

  # Socket for Dovecot clients (IMAP login, doveadm)
  unix_listener auth-client {
    mode = 0666
    user = dovecot
    group = mail
  }

  # Optional: Socket for Exim SASL authentication
  unix_listener /var/spool/exim/auth-client {
    mode = 0666
    user = root
    group = mail
  }
}

# Login process (internal)
service login {
}

# Indexer (internal)
service indexer {
}

# Anvil (rate-limiting)
service anvil {
}

create /etc/dovecot/conf.d/10-auth.conf:

auth_username_format = %{user} auth_allow_cleartext = yes auth_mechanisms = plain login auth_verbose = yes auth_debug = yes auth_debug_passwords = yes !include auth-system.conf.ext

create /etc/dovecot/conf.d/10-mail.conf:

# Dovecot 10-mail.conf mail_driver = maildir mail_path = ~/Maildir first_valid_uid = 1000 mail_access_groups = mail namespace inbox { inbox = yes separator = / }

create /etc/dovecot/conf.d/10-logging.conf:

info_log_path = /var/log/dovecot-info.log
debug_log_path = /var/log/dovecot-debug.log
mail_debug = yes
auth_verbose = yes
auth_debug = yes
log_timestamp = "%Y-%m-%d %H:%M:%S "

create /etc/dovecot/conf.d/auth-system.conf.ext:

passdb pam {
  session = yes
  service_name = dovecot
  failure_show_msg = yes
}
userdb passwd {
  fields_import_all = no
  fields {
    uid = %{passwd:uid}
    gid = %{passwd:gid}
    home = /home/%{user | username}/Maildir
    mail_driver = maildir
    mail_path = /home/%{user | username}/Maildir
  }
}

create /etc/dovecot/conf.d/15-mailboxes.conf:

namespace inbox {
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Trash {
    special_use = \Trash
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
}

create /etc/dovecot/conf.d/20-imap.conf:

protocol imap {
  mail_plugins =
}

create /etc/dovecot/conf.d/10-director.conf:

service imap-login {
  inet_listener imap {
       port = 143
  }
}
service pop3-login {
}

Finally create /etc/dovecot/dovecot.conf:

dovecot_config_version = 2.4.2
dovecot_storage_version = 2.4.2
base_dir = /run/dovecot
!include conf.d/*.conf
!include_try local.conf
protocols {
  imap = yes
  lmtp = no
}
mail_driver = maildir
mail_path = ~/Maildir
mail_uid = %{user}
mail_gid = mail
namespace inbox {
  inbox = yes
  separator = /
}
auth_username_format = %{user}

Open the /var/run/dovecot check the ownership of auth-client it should be:

ls al /run/dovecot | grep auth-client srw-rw-rw- 1 dovecot mail 0 Nov 6 10:09 auth-client

Configure the dovecot IMAP and POP3 server.