
dovecot error: mail_extra_groups
Problem
I found the following error when restarting dovecot on some servers
Restarting IMAP/POP3 mail server: dovecotWarning: mail_extra_groups setting was often used insecurely so it is now deprecated, use mail_access_groups or mail_privileged_group instead
as the error suggests you need to use another variable in the dovecot.conf other than mail_extra_groups as it is now deprecated.
Resolution
Simply edit dovecot.conf
vi /etc/dovecot/dovecot.conf
replace mail_extra_groups
mail_extra_groups = mail
with mail_access_groups
mail_access_groups = mail
restart dovecot
/etc/init.d/dovecot restart
service dovecot restart
Now the error should no longer appear