I am using the following guide: https://www.linode.com/docs/email/postfix/email-with-postfix-dovecot-and-mysql/
I followed everything, and it's a very good guide, but there is no mention of whether a user, e.g, /home/jack, needs any mailbox configuration. Do I need to do anything, such as "touch /home/jack/mbox" or add jack to a mail group, etc? Other than that, it seems like it's working for outgoing mail, but when I sent an email (via Gmail or by Gmail Smarthost configuraiton on my home laptop, I get the following error:
The recipient server did not accept our requests to connect. Learn more at https://support.google.com/mail/answer/7720
[lifepngcare.org. 2400:8900::f03c:91ff:fedb:8c14: timed out]
[lifepngcare.org. 220.127.116.11: generic::failed_precondition: connect error (111): Connection refused]
[mail.lifepngcare.org. 2400:8900::f03c:91ff:fedb:8c14: timed out]
[mail.lifepngcare.org. 18.104.22.168: generic::failed_precondition: connect error (111): Connection refused]
Any ideas given the error message? Thanks.