If you enable filter recipients who are not in the directory (along with the change to Windows 2003 outlined in http://support.microsoft.com/?kbid=842851) then you don't need to worry about legitimate misspelled email messages.
The filtering takes place at the initial SMTP communication level. The email message isn't even delivered to your server. Instead the sending server is forced to generate the NDR and the sender gets it back immediately. In my experience the sender either corrects the typo or phones in to get the correct email address. It also cuts down on the amount of garbage that the server has to deal with that are spam or virus carriers. However it is vital that you only make this change on an Exchange 2003 machine on Windows 2003 with SP1, so that you can make the change in that KB article. Otherwise your server is exposed to a directory harvest attack. Simon. -- Simon Butler MCP, MCSA, MVP:Exchange Amset IT Solutions Ltd. e: [EMAIL PROTECTED] w: www.amset-it.com w: www.amset.info -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Henry Sent: 16 March 2006 20:41 To: Exchange Discussions Subject: Problem with spoofed sender's NDRs Caught between a rock and a hard place. I just got off the Comcast Block list ( send IP address to [EMAIL PROTECTED] ). But they were counting my NDRs to spoofed comcast.net addresses as SPAM. But I need to catch mis-spelled e-mail addresses and add them as aliases. We don't tell our customers they have the wrong address, we just add them as aliases. So, how to I turn off the NDR's without losing the ability to deal with legitimate mis-spelled e-mail addresses? I know how to turn off "Filter recipients who are not in the directory" under Message Delivery Properties. So if you recommend that, what are my alternates to finding the legitimate mis-spelled e-mail addresses? Thanks, Michael _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/read/?forum=exchange To subscribe: http://e-newsletters.internet.com/discussionlists.html/ To unsubscribe send a blank email to [EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with. _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/read/?forum=exchange To subscribe: http://e-newsletters.internet.com/discussionlists.html/ To unsubscribe send a blank email to [EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] To unsubscribe via postal mail, please contact us at: Jupitermedia Corp. Attn: Discussion List Management 475 Park Avenue South New York, NY 10016 Please include the email address which you have been contacted with.
