Not practical or wise to do that. AOL, who acts like a God, does this. All the rest of us mail server admins hate AOL. If everyone played by the books, yes, that would be fine. John Tolmachoff Engineer/Consultant/Owner eServices For You -----Original Message----- From: Jason Merrique [mailto:j.merrique@xxxxxxxxxxxxxxx] Sent: Thursday, May 06, 2004 5:07 AM To: [ExchangeList] Subject: [exchangelist] RDNS: Reject on fai l http://www.MSExchange.org/ Hi All, I'd like to configure our mail server to reject email that fails an RDNS check. We're running Exchange 2003. Is this possible without a third party program? I've found the option to "Perform reverse DNS lookup on incoming messages", but not the one to reject messages that fail it. Any ideas? Cheers, Jason ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Other Internet Software Marketing Sites: Leading Network Software Directory: http://www.serverfiles.com No.1 ISA Server Resource Site: http://www.isaserver.org Windows Security Resource Site: http://www.windowsecurity.com/ Network Security Library: http://www.secinf.net/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------