I am pretty much baffled at this point on why I cant receive outside mail for my lab domain. The mx records and A records seem fine, I can ping the dns fqdn of my mail server, I can telnet to the smtp port with no problem. I can send and receive mail internally, but only send externally.I ran netdiag /fix and everything looks ok to me. A recipient policy is in plae with velifico.com listed as primary address and it has been applied to all users. The resposne I get from tryingto replyfrom my corporate exchange server is:Your message did not reach some or all of the intended recipients. Subject: RE: test-replySent: 6/17/2009 11:44 PMThe following recipient(s) could not be reached: userex1@velifico.comon6/19/200911:53 PMCould not deliver the message in the time limit specified. Please retry or contact your administrator.The response I get from trying to send from Yahoo mail is:<userex2@velifico.com>:Sorry, I couldn't find a mail exchanger or IP address. (#5.4.4)I have been unable to resolve this issue, I think it is a dns problem, please help!!

HiWhat is your mail server version?Canyou nslookup theMX record from the internet? Can you telnet the port 25 of your exchange server successfully from the internet?Theerrors seems that can'tfind out successfullythe mail server from the internet.Your mx record must apply for from ISP. The mx record is on the public DNS server, not on your private DNS server. And then, the outside mail server can Nslookup your domain, and can deliver mail to your mail server.If youhope your exchange server to receive outside mail, you must publishtheSMTP service on the internet. You alsoneed a public IP address for it.