[JPC-Shaun]

Hi;

The cause for the problem can either be because that the MX DNS record for the domain zone of destination recipient (local host) is wrong. Check whether the domain MX record in DNS name servers to verify that it’s pointing to the correct mail server. If MX record is correct, ensure that the destination domain is properly designated as the local-domain to allow Exim to know that they suppose to receive the mail without querying DNS again.