Need some more information about your Exchange setup. How many servers, what functionality, do you use smart host relay or DNS for sending external emails ? Above all, any recent changes done to Exchange SMTP virtual server settings ? Regards, Raj -----Original Message----- From: NPerez [mailto:nperez@xxxxxxxxxxxxxxx] Sent: Monday, February 02, 2004 6:16 PM To: [ExchangeList] Subject: [exchangelist] Sending Email Problem http://www.MSExchange.org/ We have Exchange 2k and running Outlook as our clients. I'm having an issue where certain emails are being returned. The error reads: "550 5.7.1 Unable to relay for user@xxxxxxxxxxx" Anyone know how to correct this? Thx! ------------------------------------------------------ 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 ------------------------------------------------------