I have this error on my exchange 2003. Is there a way to get this fixed ?
Exchange Server Errors
Event Type: Error
Event Source: MSExchangeTransport
Event Category: NDR
Event ID: 3018
A non-delivery report with a status code of 5.4.0 was generated for recipient rfc822;firstname.lastname@example.org
Causes: This message indicates a DNS problem or an IP address configuration problem
Solution: Check the DNS using nslookup or dnsq. Verify the IP address is in IPv4 literal format.
For more information, click http://www.microsoft.com/contentredirect.asp
0000: ef 02 04 c0 ï..À