Hello,

Sorry to dig up an old thread, but I wanted to get an opinion on resolving this issue.  Would it be possible to add a header to the message when it is sent from the server?  Then if you get a NDR, you could check to see if that header is in the message and reject it if it is not included.  Then you could distinguish between valid NDRs and SPAM ones.  If this is possible, any suggestions on how to build the rules for this?

Thanks very much,

Todd