MessageSure, but since I'm not an open relay at this point it doesn't have anything to do with my current problem, which is that mail sent to may domain bounces with a 5.3.5 error. Thanks, --Bob ----- Original Message ----- From: Mark Fugatt To: [ExchangeList] Sent: Thursday, July 08, 2004 5:01 PM Subject: [exchangelist] RE: SMTP Service http://www.MSExchange.org/ Did you read this one: http://www.msexchange.org/tutorials/MF005.html Mark Fugatt MCSE, MCT, Microsoft Exchange MVP Pentech Office Solutions Inc Rochester, NY Tel: 585 586 3890 Cell: 585 576 4750 http://www.4mcts.com http://www.exchangetrainer.com ------------------------------------------------------------------------------ From: Bob Grommes [mailto:bob@xxxxxxxxxxxxxx] Sent: Thursday, July 08, 2004 7:58 PM To: [ExchangeList] Subject: [exchangelist] RE: SMTP Service http://www.MSExchange.org/ Hi Thomas, Thanks for the lead. There really wasn't anything very relevant arising from a straight forward search for "SMTP Relay" (with or without quotes), however, following a long rabbit trail of links that started in a tangentially relevant article, I was able to locate a document with very relevant content about a third of the way through: www.isaserver.org/img/upl/exchangekit/2003messagescreenerintrelay/2003messagescreenerintrelay.doc One must add the domains you want to restrict receiving to, to the Domains node beneath the virtual SMTP server. I had been slogging through the properties of the service itself, and what is done with the domains is not clear from the UI or the help. Apparently, only the remote domains listed accept incoming mail, but if you have no remote domains, it accepts all comers. Strange design. Now that I've done this, and allowed anonymous connection, I can receive bounces, and I am not an open relay (not strictly -- any mail is accepted by the service, but nothing is actually forwarded for delivery unless it's addressed to my domain). However, any mails sent outright to my domain bounce with an SMTP 5.3.5 config error, which is some kind of loop back problem. Anyone have insight into that? Again, extensive Googling is not getting to the heart of this. I only have one virtual SMTP server, and no connectors to Exchange or anything else. Best, --Bob