This error appears in mail.log repeatedly after dovecot startup Notice the 777 mode for service auth I set that myself # doveconf -n # 2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.2 () # OS: Linux 5.14.17-x86_64-linode150 x86_64 Ubuntu 20.04.3 LTS # Hostname: mail.servicemouse.com auth_verbose = yes mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } plugin { sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = " imap lmtp sieve pop3 submission" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0777 user = postfix } } ssl_cert = </etc/letsencrypt/live/mail.servicemouse.com/fullchain.pem ssl_client_ca_dir = /etc/letsencrypt/live/mail.servicemouse.com ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it submission_relay_host = 127.0.0.1 submission_relay_ssl = starttls submission_relay_trusted = yes userdb { driver = passwd }