Hello,

Feb 25 20:01:15 MiniMac postfix/smtpd[433]: mysql plugin couldnt connect to any host\n

I had this message in system.log when smtpd process received an email and... I don't understand why : the email is nevertheless send.

ok I found in the old forum this dicussion :

Richard5

- the domain name whiterose.org should not be used in your main.cf,
because it also used as a virtual domain you get conflicts. Use the hostname you get from the ISP or
you local machine name for myhostname and mydomain and you won't have a conflict and still have a working mailserver.

Please make whiterose.org a virtual domain and try again.
Change the myhostname and mydomain into something different instead of the other way around as you solved it.

This resolves my problem.

Aha, I didn't know this was related, thanks for posting this info!