We are running Exchange 2003 SP2 and Exchange 2007 SP2. Clients are 2007 Outlook on the whole, but we do have some Outlook 2003 clients as well knocking around in some of the remote sites.
Almost all mailboxes are now on 2007 servers and we are in the process of decomming the 2003 environment.
From what I understand, in terms of Free/Busy information, if the mailbox is on a 2007 Server, then F/B is held within the mailbox itself. If the mailbox is on a 2003 Server, then F/B is held in the F/B Public Folder on that server. Am I correct? So the Availability service in 2007 provides F/B info directly from the mailbox. However, if the mailbox is on 2003, the Availability service will also fetch the data from Public Folders? How about if the client trying to access someone's F/B is an Outlook 2003 client? (http://technet.microsoft.com/en-us/library/aa998820(EXCHG.80).aspx
). It's the latter part that confuses me.
Also, the F/B information that is held in Public Folders? Are these replicated as part of normal PF replication? So, for instance, imagine we didn't have any 2003 Exchange servers but we did have 2003 Outlook clients - would there be F/B information held on an Exchange 2007 Public Folder somewhere? And, since we do have Exchange 2003 Servers, I assume that some 2003 Servers have F/B Public Folders - what happens when we remove these PF's?
As you can tell, I'm a little bit confused :(