I have moved from SBS 2003 to Exchange 2010 on Server 2008 R2, following that nice detailed procedure :
It has been doing very good.
Friday, mailboxes were mooved, everything looked good but we weren't able to send/receive from/to external sources. I created a send connector and everhing started to work OK.
Yesterday, I transfered the roles, and shutdown the server, and I am now faced with the same problem again.
You guys have an idea ?