I have a server running Small Business Server 2003 SP2. For the past two weeks (approx) we've been having trouble with Exchange not receiving emails from a few different people. (I know of at least 2 senders - one is from a gmail account, another from our web development company) So we know the problem isn't at the sender's end. The messages never come through to their destination, but the sender never receives an NDR - the message just disappears into thin air. I have very little experience troubleshooting exchange and was wondering if anyone can help me with how to begin troubleshooting. I know the addresses that the messages should be coming from - how would I tell whether or not the messages are actually making it to the server, and what's happening to them if they do?

I finally managed to track down a message that didn't get delivered. I looked in the message tracking center in exchange system manager, and did a search for all messages in the last hour, and there is one that I know didn't get delivered. Viewing that message's history, the last item on the list says that the message was delivered locally, but checking the user's mailbox it isn't there. Still I don't know how to troubleshoot from here. Thanks in advance

Hi,From your information, I understand that the inbounding email could not be received even though it's delivered locally from the message tracking log.Now I would like to confirm the following questions:1, Whether several receiver had this issue or just one user?2, What type of client did you use? MAPI or POP3? Please check this issue in OWA.3, Whether any error message come up in the Application event log?ThanksAllen

I'm using Exchange 2003 SP2 server too and have the same kind of problem. I did some investigations and found a potential cause. Would you mind checking my post and telling me if it's similar? http://social.technet.microsoft.com/Forums/en-US/exchangesvrgeneral/thread/90fc865f-bfb8-4f05-8a7a-c2a694cb4edd