I am moving from an old Exchange 2003 server to a clean install on new hardware. Plan on using the "move mailbox" wizard in ESM. From what I've read it looks like it SHOULD be fairly smooth sailing, but I'm wondering about the clients. Most use Cached Exchange Mode and connect from outside the network (via RPC over HTTPs). I know how to reconfigure the registry keys on the new Exchange server and on the GC on the network to ensure RPC over HTTPs continues to function properly.
What I'm wondering though is if each user will be forced to redownload all of their email? In other words, will moving the mailbox to another server somehow invalidate their current OST file and force them to regenerate it? Since they're clients on the internet, that could really bog down the internet connection in the main office.
My hope is that it will just continue as it did before and only download changes to their mailbox since they last opened Outlook. Anyone done this before and can verify how it will behave?