Unknown senders in outgoing mail queue

Posted on 2006-07-18
Last Modified: 2012-06-21
We have about 900 unknown senders in outgoing mail queue. We are running Exchange 2003 on Windows 2003. We have been blacklist from some mail servers already. How can I delete the unknown senders in the mail queue? How can I prevent this from happening? How can I find the problem?
Question by:mariani_500
  • 2
LVL 104

Accepted Solution

Sembee earned 100 total points
ID: 17134123
Go and look at my spam cleanup article

That will help you identify what type of messages they are and then how to clean them up.


Author Comment

ID: 17139489
I'm worried about "Directory Harvest" attacks! Is there any other way around this. Can this be a Trojen? Thanks!
LVL 104

Expert Comment

ID: 17141156
A directory harvest attack is dealt with using the recipient filtering options that the article mentions. You need to ensure that you have Windows 2003 SP1 installed and enable the tarpit option.

I would be very surprised if it was a trojan. Too conspicuous. Trojans and viruses don't go looking for an SMTP server to send their crap through. They have their own SMTP engine. Using another makes it too easy to find.


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