In an Exchange 2003 to 2010 migration that is happening over several months. At what time is it safe to do the following? Before they have moved mailboxes? During? After? Before they have migrated the Public Folders? During? After?
We don’t want to do it and cause problems for users on the old 2003 Exchange Server (that is also still receiving email for the domain). But we also don’t want to limit functionality for users who have been migrated.
upgrade the address list by running
Set-AddressList “All Users” -IncludedRecipients Mailboxusers Next upgrade all groups default address list Set-AddressList “All Groups” -IncludedRecipients MailGroups
It doesn't really matter where in the process you upgrade address lists, EAPs of GAL. The reason you need to convert them is to be able to manage them in Exchange 2010.