I have a cleint that's has there email returned everytime they send me something. No one else seems to have the problem. I have not problem sending them email but it they reply it bounces back. This is getting very fustrating on both ends. The following are the steps I have done so far:1. Turned off SpamHaus on my exchange server2. Added their domain as a save sender3. Shut off Tar PittingThe following is the header information from one of the emails that was returned:Microsoft Mail Internet Headers Version 2.0 From: postmaster@processfab.com To: mario.arriaga@processfab.com Date: Sat, 20 Feb 2010 04:23:41 -0800 MIME-Version: 1.0 Content-Type: multipart/report; report-type=delivery-status; boundary="9B095B5ADSN=_01CA90033906D57200007416processfab.com" X-DSNContext: 7ce717b1 - 1418 - 00000004 - C00402D1 Message-ID: <FRaqbC8wS00000367@processfab.com> Subject: Delivery Status Notification (Delay) --9B095B5ADSN=_01CA90033906D57200007416processfab.com Content-Type: text/plain; charset=unicode-1-1-utf-7 --9B095B5ADSN=_01CA90033906D57200007416processfab.com Content-Type: message/delivery-status --9B095B5ADSN=_01CA90033906D57200007416processfab.com Content-Type: message/rfc822 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/related; type="multipart/alternative"; boundary="----_=_NextPart_001_01CAB1C2.BE88C859" X-MimeOLE: Produced By Microsoft Exchange V6.5 Subject: RE: tag on Date: Fri, 19 Feb 2010 16:22:10 -0800 Message-ID: <AEDAA669538EED41B8BD8F9F32CD55D05ABE1D@SBS.pfi.local> X-MS-Has-Attach: yes X-MS-TNEF-Correlator: Thread-Topic: tag on Thread-Index: AcqxwkibDdSFDdGmR+SGu3Aq14wQygAAGxDQ From: "Mario Arriaga" <mario.arriaga@processfab.com> To: "Todd M. Gallagher" <TGallagher@ApexSkypark.com> Cc: "Mike Burdge" <MDBurdge@processfab.com> ------_=_NextPart_001_01CAB1C2.BE88C859 Content-Type: multipart/alternative; boundary="----_=_NextPart_002_01CAB1C2.BE88C859" ------_=_NextPart_002_01CAB1C2.BE88C859 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable ------_=_NextPart_002_01CAB1C2.BE88C859 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable ------_=_NextPart_002_01CAB1C2.BE88C859-- ------_=_NextPart_001_01CAB1C2.BE88C859 Content-Type: image/gif; name="image002.gif" Content-Transfer-Encoding: base64 Content-ID: <image002.gif@01CAB17F.B0349740> Content-Description: image002.gif Content-Location: image002.gif ------_=_NextPart_001_01CAB1C2.BE88C859-- --9B095B5ADSN=_01CA90033906D57200007416processfab.com--

Hi, I would probably turn on SMTP logging on their sending server and see why it can't connect to your server. While on their server I might also just try and telnet to your server, mail.apexskypark.com, on port 25 and try and manually compose a message through telnet and see if it goes through.Is either you or your client on Exchange Online?ChadChad Mosman, MessageOps | www.MessageOps.com

Hi, I agree with Chad, please check SMTP log of sender side to see if you can find some clues. In sender side, please use telnet to see if you can send a test email. XFOR: Telnet to Port 25 to Test SMTP Communication http://support.microsoft.com/?id=153119 Could you please paste the NDR here? Thanks, Elvis