If I eliminate NDRs completely for invalid addresses, though, then people who make innocent typing mistakes will not know that their message did not get through.
...... I re-read KB909005, and I missed the part about NDRs still being generated but pushing it back to the sending server before accepting the message. I think that will work. Thanks, Kyle B. Plummer ________________________________ From: Don Andrews [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 18, 2008 11:53 AM To: MS-Exchange Admin Issues Subject: RE: NDR attachment stripping or recipient filtering - which is better? I'd think recipient filtering as long as it's done at the front door would eliminate NDRs for invalid addresses. ________________________________ From: Michael B. Smith [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 18, 2008 8:44 AM To: MS-Exchange Admin Issues Subject: RE: NDR attachment stripping or recipient filtering - which is better? Stop sending NDRs? Regards, Michael B. Smith MCSE/Exchange MVP http://TheEssentialExchange.com From: Kyle Plummer [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 18, 2008 11:42 AM To: MS-Exchange Admin Issues Subject: NDR attachment stripping or recipient filtering - which is better? I'm using Exchange 2003 and am trying to keep my domain from participating in NDR flood attacks. I've identified two possible methods: NDR attachment stripping, or recipient filtering paired with SMTP tar pitting. Any preference as to which is better, or are there other methods to fight this crud? Thanks in advance, Kyle B. Plummer ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~