You should start a new thread, not co-opt an existing one. Yes or yes. You can configure Exchange to not accept valid email addresses (see "Recipient Filtering" in the online help) and you can configure Exchange to accept them but not generate bounces (see "Configure Message Defaults" in the online help). From: exchangelist-bounce@xxxxxxxxxxxxx [mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of Jabber Wock Sent: Tuesday, October 24, 2006 7:45 AM To: exchangelist@xxxxxxxxxxxxx Subject: [ExchangeList] Re: I NEED TO GRIPE! Hi, Does Exchange 2003 reject unconfigured email addresses in the SMTP conversation, or does it accept and then bounce (backscatter)? Is there a way to confgure Exchange 2003 to ensure no backscatter? JW