Helo, The issue is I am not able to send email to the domain saigonco-op.com.vn from my exchange email. But can send from other emails systems like yahoo etc. Getting NDR: #550 4.4.7 QUEUE.Expired; message expired ## While trying to send email from telnet session, I am getting the following issue: RCPT TO:phong-hv@saigonco-op.com.vn 450 4.7.1 <fqdn>: Helo command rejected: Host not found Same error can also get from send connector protocol logs Kindly help ManuRegards from www.windowsadmin.info | www.blog.windowsadmin.info

Hi, See if this helps: http://social.technet.microsoft.com/Forums/en/exchangesvrgeneral/thread/49f4fcb7-4f1c-40ad-ba37-7bd4c4cba8ee Leif

On Mon, 10 Oct 2011 08:56:20 +0000, ManU PhiliP wrote: >The issue is I am not able to send email to the domain saigonco-op.com.vn from my exchange email. But can send from other emails systems like yahoo etc. > >Getting NDR: > >#550 4.4.7 QUEUE.Expired; message expired ## > > While trying to send email from telnet session, I am getting the following issue: > >RCPT TO:phong-hv@saigonco-op.com.vn 450 4.7.1 <fqdn>: Helo command rejected: Host not found What data did you put into the HELO command? Whatever you used, it must be found in a publically accessible DNS. >Same error can also get from send connector protocol logs So what does your server put into the HELO or EHLO it sends? It should be sending the FQDN for the IP address it uses when it sends e-mail to other Internet servers. I'm going to guess that it's using an internal name, like myserver.mydomain.local. Change the FQDN of the sned connector to use name.domain.com (or whatever name is applicable). --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

On Mon, 10 Oct 2011 08:56:20 +0000, ManU PhiliP wrote: >The issue is I am not able to send email to the domain saigonco-op.com.vn from my exchange email. But can send from other emails systems like yahoo etc. > >Getting NDR: > >#550 4.4.7 QUEUE.Expired; message expired ## > > While trying to send email from telnet session, I am getting the following issue: > >RCPT TO:phong-hv@saigonco-op.com.vn 450 4.7.1 <fqdn>: Helo command rejected: Host not found What data did you put into the HELO command? Whatever you used, it must be found in a publically accessible DNS. >Same error can also get from send connector protocol logs So what does your server put into the HELO or EHLO it sends? It should be sending the FQDN for the IP address it uses when it sends e-mail to other Internet servers. I'm going to guess that it's using an internal name, like myserver.mydomain.local. Change the FQDN of the sned connector to use name.domain.com (or whatever name is applicable). --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Hi ManU PhiliP, Any update for your issue? It could be cuased by the FQDN of send connector point to non-public FQDN . Above gave some good information. What is your ptr record, and then confirm the the FQDN configured in the send connector. Regards! Gavin TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.