I am trying to migrate a domain to receive emial by SMTP, currently they use POP accounts. When I try to send an email to this domain from any other domain, the server of the sending domain returns the error:
You do not have permission to send to this recipient. For assistance, contact your system administrator.
<junosbs.JunoUKLtd.local #5.7.1 smtp;550 5.7.1 Unable to relay for firstname.lastname@example.org>
The server responsible for the email at davidcollinge.co.uk is configured to allow connections from any computer and outgoing email is fine. I have tried relay permissions for users but this made no difference.
I am out of ideas.