Hello, we are about to remove the Exchange 2003 structure from our organisation (don't worry we have an Exchange 2010 infrasturcture). My quetsions are: 1) do I have to migrate the smtp, System Attendant and the System Mailbox to the new Exchange 2010 (if possible) 2) We still have some distribution groups that still have an x400 adress pointing to the old Exchange 2003 AD structure. How do I upgrade them to the new one and what happens to all Object the have a link to the old Exchange 2003 AD structure? Regards

1) No, you do not need to move those mailboxes to 2010 2) You need to upgrade your email address policies for 2010. In that process, you will give those distribution groups an smtp address. When Exchange 2003 is removed, the Administrative Group will remain in Active Directory, so everything will work. Please see these for proper removal of Exchange 2003: http://technet.microsoft.com/en-us/library/gg576862.aspx http://www.simple-talk.com/sysadmin/exchange/upgrade-exchange-2003-to-exchange-2010/ The most important thing to do when removing Exchange 2003 is to get your Public Folders oved over correctly. Very critical to get this correct, otherwise you will be manually editing things in Active Directory using ADSIEdit.MCITP Exchange 2010 | MCTS Exchange 2007 | MCITP Lync Server 2010 | MCTS Windows 2008 | MCSE 2003

Thanks for help. Just for me, that means the x400 adress in Exchange 2010 are not in use anymore, so smtp would be enough. Regards