hi all i have a exchange server 2003 , recently i have found out some people outside using my exchange as a relay to send mail out, but i have not set open relay, and there are so many mail queues in exchange server, the mail address who using my exchange server as a relay is from yahoo.com , any idea how to prevent such problem ? thanks ! keith

hi,please look at here for your issue;http://technet.microsoft.com/en-us/library/bb123843(EXCHG.65).aspxhttp://support.microsoft.com/kb/895853/en-usregards,Mumin CICEK | Exchange - MVP | www.cozumpark.com | www.mumincicek.com

Hi ,You can use the below link to prevent Exchagne 2003 and 2003 from relayinghttp://www.petri.co.il/preventing_exchange_2000_2003_from_relaying.htmRegards,Krishna

In the event that you have configured Exchange to not relay and you find that the email address @ yahoo.com is still relaying (via Phishing) try this:1. One of your users may have responded to a phishing email and given their credentials2. Phisher comes in via OWA (if published externally) and places items in the drafts folder and sets up rules to trigger relays (not real relays as it comes from an internal account)This happened to us and if you are in the same situation you need to open the user(s) mailbox and delete the unknown draft emails and remove the rules.Scott