Hi,When we try to send an e-mail to particular domain from our exchange, it get bounce back with the following error message.Your message did not reach some or all of the intended recipients. Subject:Follow up Sent:9/23/2009 9:36 AM The following recipient(s) cannot be reached: first.last@recipientDomain.com.sg on 9/23/2009 9:37 AM There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. <ExSrvName.ourDomain.com #5.5.0 smtp;550-Verification failed for <name@ourDomain.com>>Not for all, but to certain domains. When we send to them using gmail or hotmail, they can receive it.I have done some research and found solution that work for others.But I don't know how to apply it to my case.Below is the link to the forum where I found the solution.http://www.ozzu.com/hosting-forum/email-problem-550-verification-failed-t20812.htmlBelow is the solution that the user has posted.I just want to let you guys know that I have resolved the problem and here is what I did. Apparently it wasn't liking the fact that the primary nameserver and the and the actual hostname of the server were the same. All I did was change the hostname to another routable domain name such as mail.somedomain.com and made sure all the mx records were in place. That seemed to have resolve the problem. I have tested sending emails to all the hosts that have previously rejected them, and no emails bounced back. In fact I got a few responses now from them which confirms it is fixed. I have looked all across the Internet and have now found a resolution like this listed, so hopefully this helps someone else in the future. To change the hostname of the server I typed in SSH (logged in as root user): hostname mail.somedomain.com I then also made sure that mail.somedomain.com came right after localhost. So in other words it looks something like: 127.0.0.1 localhost.localdomain localhost 55.555.55.5 mail.somedomain.com Best Regards, TripleS

Below is the result of our DNS report.CheckDNS.NET is asking root servers about authoritative NS for domain Got DNS list for 'ourdomain.com' from a.gtld-servers.net Found NS record: ns1.shopco.com[216.40.47.80], was resolved to IP address by a.gtld-servers.net Found NS record: ns2.shopco.com[64.98.148.14], was resolved to IP address by a.gtld-servers.net Domain has 2 DNS server(s) CheckDNS.NET is verifying if NS are alive DNS server ns1.shopco.com[216.40.47.80] is alive and authoritative for domain ourdomain.com DNS server ns2.shopco.com[64.98.148.14] is alive and authoritative for domain ourdomain.com 2 server(s) are alive CheckDNS.NET checks if all NS have the same version All 2 your servers have the same zone version 8675310 CheckDNS.NET is verifying if NS are alive NS list mismatch: registration authority reports that domain is hosted on the following servers: 'ns1.shopco.com; ns2.shopco.com', but DNS server ns1.shopco.com reports domain to be hosted on 'ns1.shopco.com'. Please make sure that you configure the same DNS servers in registrar database and on your DNS CheckDNS.NET verifies www servers Checking HTTP server www.ourdomain.com [202.63.130.146] HTTP server www.ourdomain.com[202.63.130.146] answers on port 80 Received: HTTP/1.1 302 Object Moved Location: http://www.ourdomain.com/Pages/default.htm Your main page redirects to another location. Several search engines will be unable to index your site. CheckDNS.NET tests mail-servers Domain ourdomain.com has only one mail-server Checking mail server (PRI=0) 202.63.130.146 [202.63.130.146] Mail server 202.63.130.146[202.63.130.146] answers on port 25 <<< 220 EXSRV1.ourdomain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.3959 ready at Thu, 24 Sep 2009 16:43:57 +0800 >>> HELO www.checkdns.net <<< 250 EXSRV1.ourdomain.com Hello [195.60.98.253] >>> MAIL FROM: <dnscheck@uniplace.com> <<< 250 2.1.0 dnscheck@uniplace.com....Sender OK >>> RCPT TO: <postmaster@ourdomain.com> <<< 250 2.1.5 postmaster@ourdomain.com >>> QUIT Mail server 202.63.130.146 [202.63.130.146] accepts mail for ourdomain.com Best Regards, TripleS

Hi,Why am I getting no response from forum?I have been told by POTC that we will get response within 8 hrs.This problem is getting a bit cranky because we are currently in need of contacting with particular user from other domain and all emails from our exchange server bounced back to us. Best Regards, TripleS

Hi, Looks like your MX/A and PTR records are different. I suggest you try checking your PTR records on internet. You can use few websites like www.network-tools.com, Select lookup and type the PUblic IP address of SMTP gateway. the Result should come with your domain name. The Domain names of A records (which is Pointed by MX Record) and PTR records results shoule match. If it does not exist then talk to your ISP. Hope this helps. Thanks.Vishal Ramnani | MCITP - Exchange 2007 | MCSE Messaging | MCTS - Win 2008 Config

Hi,From the description, it seems that the destination server blocked the email due to security policy.Please try to send the testing email by using telnet in order to diagnose this issue.http://support.microsoft.com/kb/153119What's the result?ThanksAllen

The result is the same.I tried to send to different recipient.I used RCPT TO:user@otherdomain.com.sg notify=success,failureFor every successful e-mail I got this message to my Inbox.FromSubjectReceivedSizeCategoriesSystem AdministratorDelivered: subject is here2:40 PM6 KB Your message To: Unknown Subject: subject is here Sent: 10/1/2009 2:39 PM was delivered to the following recipient(s): Support on 10/1/2009 2:40 PM For every unsuccessful e-mail I got this message to my Inbox. (previously bouncing back to my address when tried to send normally from outlook) Your message did not reach some or all of the intended recipients. Subject: hello Sent: 10/1/2009 2:49 PM The following recipient(s) cannot be reached: kellie.liew@otherdomain.com.sg on 10/1/2009 2:49 PM There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. <EXSRV1.our-domain.com #5.5.0 smtp;550-Verification failed for <susu.soe@our-domain.com>> Any Idea what could be the problem between our domain and theirs.We have our own primary DNS and secondary DNS as well as ExchangeServer. Best Regards, TripleS

Hi,I've talked to our ISP provider and been told that their side is only responsible for providing the connection to us.If we can connect to the Internet, their side cannot do anything.What do you reckon ISP can do for us if we are facing this problem? Best Regards, TripleS

Hi,For this issue, we need to contact the remote server (particular domain) rather than our ISP to confirm why they block your email.ThanksAllen

Contact the remote domain admin and have him whitelist your sending ip/domain. also check your domain in case if it is blacklisted http://www.mxtoolbox.com/blacklists.aspx Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|