Every now and then some of my users complain that they have received an Undelivered email report from the administrator, to an email that they have not sent. I have checked the email's content and traced the message on the server but I cannot find out a clear justification of how they received the message, the message is as follows:
Your message did not reach some or all of the intended recipients.
Subject: RE: MensHealth id 104964
Sent: 3/14/2008 9:49 PM
The following recipient(s) cannot be reached:
firstname.lastname@example.org on 3/14/2008 9:49 PM
The e-mail account does not exist at the organization this message was sent to. Check the e-mail address, or contact the recipient directly to find out the correct address.
I have checked the domain and it is not registered.
Is there a way I can stop this type of spam? is IMF the answer, and how? Is there a setting in Exchange 2003 to validate the originator of the message? Is there a log file in exchange that can provide me with more information on a specific message, such as IP of sender etc …