hubertbunio wrote:
Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain xxxxxxxx.co.uk by mx0.123-reg.co.uk. [94.136.40.61].
The error that the other server returned was:
550 This domain is not hosted here
Is the IP address same as defined in DNS? Is it your iRedMail server?
Error message "550 This domain is not hosted here" is not generated by Postfix or its policy servers, i don't think this server runs iRedMail.