You have to specify on outlook express on the mac that you want to use authenticated SMTP. Just like you would put a username and password in for receiving POP3 you need to put in a username and password for the SMTP. If your current version of express on the mac doesn't have that then download the latest version. -----Original Message----- From: Chris [mailto:ccerer@xxxxxxxxxxxx] Sent: Monday, July 15, 2002 9:32 AM To: [ExchangeList] Subject: [exchangelist] Relaying prohibited for Macintosh client http://www.MSExchange.org/ I have recently secured my Exchange 2000 server from being an open relay. I have a Mac on my network that uses Outlook Express for a mail client. Since fixing the open relay issue, once in a while the Mac can't send mail, and recieves the "cannot relay for personA@xxxxxxx" or similar error message. I believe that it's probably due to the fact the the mac doesn't log on to the domain, so perhaps the server won't process the mail because it doesn't recognize it? Any help would be greatly appreiciated! Chris ------------------------------------------------------ You are currently subscribed to this MSExchange.org Discussion List as: jrobill@xxxxxxxxxxxxx To unsubscribe send a blank email to $subst('Email.Unsub')