Hello, currently I have both Exchange 2007 and Exchange 2010 working. Half of the mailboxes have been transitioned to Exchange 2010. I made a test to see if I was able to complete the mailbox transition and shutdown Exchange 2007 by shutting down all Exchange 2007 services. With only Exchange 2010 working I managed to: send internal and external emails, receive internal emails but NOT external emails. The only problem then was when receiving external emails. Do you have any idea of why this was not working? Because as soon as I turned on Exchange 2007 services I received all the external emails pending. Is there any way of set a 'Master' mail server or so? Thanks in advance.

What is currently the hop between the internet to Exchange (nothing, SPAM solution, Edge server)? You will need to create a receive connector that allows that last hop to send to your exchange server. Then you will have to either modify your firewall to allow inbound smtp traffic or modify the hand-off IP of whatever is the last hop device. http://technet.microsoft.com/en-us/library/bb125159.aspxTim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

Where were the messages pending? In the queue viewer of the Exchange 2010 server? Or are you looking somewhere else? It isn't clear from the question. Simon.Simon Butler, Exchange MVP. http://blog.sembee.co.uk , http://exbpa.com/

Thank you. Between internet and exchange is only the firewall. The receive connectors in Exchange 2010 are configured as the ones in Exchange 2007. Firewall was also allowing smtp connection (as through telnet I was able to connect). What else could it be?

Did you change the firewall rule to translate the public IP where email is coming in to point to 2010 HUB server? It is probably still pointing at 2007 server. Did you create a specifc receive connector or just enabling anonymous on the Default connector?Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

There was nothing on exchange 2010 queue. When I started Exchange 2007 services I was ables to see there for a sec the stucked emails.

I have there 2 connectors (one for por 25 and the other one for por 587). The firewall is performing NAT over exchage 2010.

So it sounds like you are trying to use the Defaul receive connector. If you want to use the Default connector, you will have to enable anonymous users on the permission Groups tab. http://technet.microsoft.com/en-us/library/bb738138.aspx I always vote for leaving my default connectors alone and creating new ones for specific scenarios (like this one) Another thread: http://social.technet.microsoft.com/Forums/en-US/exchangesvrdeploy/thread/75c9f5f8-46d3-4bed-bdf2-79c0c6bcf0d1 Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

Something Silly, but just in case for someone having this problem: MX records were not properly set.

Hi John Then definitely there is problem in receiving mail from internet. Thanks Amit Haridas