Dear all, I'm unsure if this question have been asked & answered before but this issue have really put me in a jam and seriously in need of assisstance. My company is running MS Exchange 2003 for its email service. Everything was working fine until recently where any new "user" created in the AD cannot receive external email. Those old account have no problem what-so-ever. Those users facing the problem can send & receive email locally and have no problem sending email externally. Their only problem is that they cannot receive external emails. Anybody has any ideas? Thanks in advance.

Start with making sure that the new users have all the email addreses they should. Does the senders get an NDR of some sort?

They're are all assigned to their respective mailboxes (otherwise they wouldn't be able to receive their local emails at all right?) Anyway, here's a sample of the NDR I got when I tried to send one of the unlucky staff an email from my Yahoo Email. Hi. This is the qmail-send program at yahoo.com. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out. <fairuz.aziz@pyrogen.com.my>: 202.75.39.158 does not like recipient. Remote host said: 550 <fairuz.aziz@pyrogen.com.my> No such user here Giving up on 202.75.39.158.

The reason I asked about email addresses is that some organizations use internal domains like .local and if that address is properly generated the internal mail-flow would work correctly even if the addresses based on the external domains where missing. The NDR clearly states that the receving server doesn't recognise the new address. Are you absolutely sure about the address generation? Sorry for asking again but i just want to make sure that they are ok... Are you using any anti-spam software or appliance that uses AD to check if a user excist? If so, does it use a scheduled sync to fetch users that could cuse the software to deny addresses that hasn't been synced yet? Just a thought...

On Wed, 7 Apr 2010 08:28:23 +0000, Bombarder wrote:>>>They're are all assigned to their respective mailboxes (otherwise they wouldn't be able to receive their local emails at all right?) Anyway, here's a sample of the NDR I got when I tried to send one of the unlucky staff an email from my Yahoo Email. >> Hi. This is the qmail-send program at yahoo.com. >I'm afraid I wasn't able to deliver your message to the following addresses. >This is a permanent error; I've given up. Sorry it didn't work out. >><fairuz.aziz@pyrogen.com.my>: >202.75.39.158 does not like recipient. >Remote host said: 550 <fairuz.aziz@pyrogen.com.my> No such user here >Giving up on 202.75.39.158. The IP address 202.75.39.158 isn't your Exchange server. Is it yourISP's SMTP relay? If it is, how do you inform them of new e-mailaddresses that they should accept on your behalf?---Rich MatheisenMCSE+I, Exchange MVP--- Rich Matheisen MCSE+I, Exchange MVP

Same here!! I have the exactly same problem. I am using Exchange 2007.

The message I get is below: Delivery to the following recipient failed permanently: whobbs@thehighlonesomeranch.com Technical details of permanent failure: Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 No such user - psmtp (state 14). ----- Original message ----- MIME-Version: 1.0 Received: by 10.216.89.140 with SMTP id c12mr2517512wef.163.1273606039188; Tue, 11 May 2010 12:27:19 -0700 (PDT) Received: by 10.216.53.142 with HTTP; Tue, 11 May 2010 12:27:19 -0700 (PDT) Date: Tue, 11 May 2010 14:27:19 -0500 Message-ID: <AANLkTilQ2tCkWcZTDh62hQPk8g9oyYM65goUdLQdMXaP@mail.gmail.com > Subject: test From: Susu Liao <susuliao@gmail.com > To: whobbs@thehighlonesomeranch.com Content-Type: multipart/alternative; boundary= 0016e6d784758cbc570486568351

I just started experiencing this problem today on our Exchange 2007 servers. Anyone found a solution to this? External mail continues to flow in to existing mailboxes, but the two new ones I created today can only receive internal message and they can send to external recipients, but when a reply is attempted to them, the NDR says User unknown.

On Thu, 9 Sep 2010 17:29:38 +0000, SuzB wrote: > > >I just started experiencing this problem today on our Exchange 2007 servers. Anyone found a solution to this? > > External mail continues to flow in to existing mailboxes, but the two new ones I created today can only receive internal message and they can send to external recipients, but when a reply is attempted to them, the NDR says User unknown. Are you using Edge servers? Have the new mailboxes (in the AD) been sync'd with the directory on the Edge servers? IIRC the EdgeSync only runs once every four hours. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP