Our ISP stated that our SMTP port activity was real high and that they had received complaintsAfter some research I found that we had 15000 Bad Mails a day. Thus we were sending outNDR to other Servers via the internetSteps taken to solve the issue1.Under Global Settings --> Internet Message Formats --> Default --> Properties -->Advanced TabUnchecked "Allow delivery reports, "Allow non-delivery reports"The only option that is selected here is "Preserve sender's display name on message"2. Created a mail enabled group called "No internet Email" and added the postmaster account to that group3. Created a connecter called "Default SMTP connector" and associated theDefault SMTP Virtual Server to that connector.4. Added the group to the "Reject messages from:" Thus stopping the postmaster accountfrom sending out NDRs to other server in an effort to slow down out going traffic.Results:SMTP outside traffic has slowed down.Issue:The bad mail server is still filled with NDR but only 100 a dayThe Queue is filled outgoing emails with a Connection State of Retry I figure out that reverse non-delivery report attack is my issue. I read the following articlehttp://support.microsoft.com/kb/909005but the steps involved relate to a fix for exchange 2003. How can I solve this issue under exchange 2000? my eyes are tired of researching this issue so maybe I missed something.

Hi I have the same issue, i you found a solution let me know, i will in return. Aziz

You can install a never version of Exchange and use that server as a gateway for your mail.Vamsoft has a low prised spam protection for Exchange SMTP http://www.vamsoft.com/. the price is really good to.