While I was investigating my phantom hard drive space issues. I decided to turn on the monitor for SMTP and after I did a started getting frequent MSExchangeTransport, Event ID 7004 entries in my application log. Well over 100 entries over a 4 hour time frame. The event explanation points to a connectivity issue, but we haven’t had any.
On a possibly related note, I checked the message queue, and there are about 300 messages listed. The domains appear to be for junk/spam mail – several listings for the same domain name with different extentions ( net.pk, net.tw), etc.
I have non-authenticated relaying turned off. Should I not allow any relaying at all? Under SMTP access settings I have allow Anonymous, Basic Auth and Integrated Windows.
Is there anything else I need to look for or reconfigure?
Exchange 03 on Server 03, behind a firewall with port 25 and 443 (for OWA) pointing to this machine. No POP3 or IMAP access is used.